PDF document

- 1 -

                     2024 Form 6 Instructions for Combined Returns 
 
Who Must File  Form 6 ............................................................................................................................................. 2 
 Types of Taxpayers .................................................................................................................................................................2 
 “Doing Business in Wisconsin” ................................................................................................................................................2 
 Entities Not Required to File ....................................................................................................................................................3 
 Exempt Entities ........................................................................................................................................................................3 
 Franchise or Income Tax .........................................................................................................................................................4 
 Economic Development Surcharge .........................................................................................................................................4 
Separate Return or Combined Return? ................................................................................................................. 4 
 Combined Returns and Groups in General ..............................................................................................................................5 
 Test 1: Commonly Controlled Group........................................................................................................................................5 
 Test 2: Unitary Business ..........................................................................................................................................................6 
 Test 3: Water’s Edge ...............................................................................................................................................................7 
General Franchise or Income Tax Return Instructions ........................................................................................ 8 
 Who is the “Designated Agent?” ..............................................................................................................................................8 
 When and Where to File ..........................................................................................................................................................8 
 Period Covered by Return .......................................................................................................................................................9 
 Accounting Methods and Elections ........................................................................................................................................ 10 
 Payment of Estimated Tax ..................................................................................................................................................... 11 
 Components of Combined Return ......................................................................................................................................... 11 
 Required Disclosures and Information Returns ..................................................................................................................... 11 
 Internal Revenue Service Adjustments, Amended Returns, and Claims for Refund .............................................................. 12 
 Final Return ........................................................................................................................................................................... 13 
 Penalties for Not Filing or Filing Incorrect Returns ................................................................................................................. 14 
Conformity with Internal Revenue Code and Exceptions .................................................................................. 14 
 Provisions of the Internal Revenue Code Not Adopted by Wisconsin: ................................................................................... 15 
 Other Exceptions to Internal Revenue Code .......................................................................................................................... 18 
 Depreciation and Bonus Depreciation ................................................................................................................................... 18 
 Section 179 Expense ............................................................................................................................................................. 19 
 Capital Losses ....................................................................................................................................................................... 19 
 Limitations on Certain Federal Deductions ............................................................................................................................ 19 
 Federal Consolidated Return Regulations ............................................................................................................................. 19 
 Differences Between Federal and Wisconsin Basis of Assets ............................................................................................... 19 
General Instructions for Apportionment ............................................................................................................. 19 
 Who Must Use Apportionment ............................................................................................................................................... 20 
 Apportionment Method........................................................................................................................................................... 20 
 Nonapportionable Income ...................................................................................................................................................... 21 
 Separately Apportioned Income ............................................................................................................................................. 21 
 Corporate Partners or LLC Members ..................................................................................................................................... 21 
 Separate Accounting.............................................................................................................................................................. 21 
 Treatment of Specialized Industries and Entities ................................................................................................................... 22 
 Foreign Sales Corporations (FSCs) ....................................................................................................................................... 22 
 Interest Charge Domestic International Sales Corporations (IC-DISCs) ................................................................................ 22 
 Insurance Companies ............................................................................................................................................................ 22 
 Personal Holding Companies ................................................................................................................................................ 22 
 RICs, REMICs, REITs, and FASITs ....................................................................................................................................... 22 
 Tax Exempt Organizations ..................................................................................................................................................... 22 
Line-by-Line Instructions for Form 6, Page 1 ..................................................................................................... 22 
 Form 6, Page 2 ...................................................................................................................................................................... 27 
 Part I: Modified Federal Taxable Income ............................................................................................................................... 29 
 Part II: Unitary Income Computation ...................................................................................................................................... 32 
 Part IV:  Wisconsin Net Business Loss Carryforward ............................................................................................................ 46 
 Part V:  Nonrefundable Credits .............................................................................................................................................. 50 
 Part VI:  Additional Member Information ................................................................................................................................ 52 
Required Attachments ........................................................................................................................................... 55 
 Web Resources .................................................................................................................................................................... 56 
 Contact Information ............................................................................................................................................................. 56 
 Obtaining Forms .................................................................................................................................................................. 56

- 2 -

Enlarge image

                                 2024 Form 6 Instructions for Combined Returns 
 
IMPORTANT:    Unless  otherwise noted, every combined return must include  the following supplemental 
forms/schedules in addition to Form 6: 
•  Apportionment information for each member of the combined group, Schedule A-01 to A-11 
•  Federal Form 1120, U.S. Corporation Income Tax Return, for each member of the Wisconsin combined group 

Who Must File 2024 Form 6

Types of Taxpayers 

Form 6 is only for corporations that are required to file as a combined group.  
Corporations that must file Form 6, if not otherwise exempt, include: 
•  Corporations doing business both in and outside Wisconsin (multistate corporations) 
•  Corporations that are members of combined groups doing business in Wisconsin 
•  Domestic insurance companies doing business in Wisconsin 
Corporations (other than insurance companies) that are not part of a combined group file Form 4.  
•  Tax-option (S) corporations file Form 5S.  
•  Tax exempt corporations may be required to file Form 4T.  
Additionally, some corporations must file a Wisconsin corporation franchise or income tax return (Form 4, 5S, or 4T, 
as applicable) regardless of whether they are otherwise “doing business in Wisconsin.” These corporations include: 
•  Corporations organized under Wisconsin law 
•  Foreign corporations licensed to do business in Wisconsin 
•  Foreign corporations that are the sole owner of an entity that is disregarded as a separate entity under IRC 
   section 7701 and does business in Wisconsin 
•  Foreign corporations engaged in buying or selling lottery prizes if the winning tickets were originally bought in 
   Wisconsin 

Doing Business in Wisconsin 

Doing business in Wisconsin means that the corporation has “nexus” with Wisconsin. Activities that create nexus 
include the following: 
•  Maintaining any business location in Wisconsin 
•  Owning real estate in Wisconsin 
•  Ownership of tangible personal property in Wisconsin, including inventory held by a distributor, consignee, or 
   other non-employee representative, whether or not used to fill orders for the owner's account, but not including 
   personal property for use in an employee's or representative's home, residential office or automobile that is solely 
   limited to conducting the activities protected by P.L.86-272 
•  Regular activity in Wisconsin by employees or representatives soliciting orders with approval authority  
•  Regular activity in Wisconsin by employees or representatives performing services related to the sale of tangible 
   personal property. Services related to the sale of tangible personal property may include consulting, design, 
   engineering, construction, installation, and assembly of equipment 
•  Regular activity in Wisconsin by employees or representatives engaged in purchasing activities, credit investiga-
   tions, collection of delinquent accounts, or conducting training or seminars for customer personnel in the opera-
   tion, repair, or maintenance of the taxpayer's products 
•  Operation of mobile stores in Wisconsin, such as trucks with driver-salespersons, regardless of frequency, or 
   whether the driver-salesperson is an employee 
•  Leasing of tangible property in Wisconsin, but not including personal property for use in an employee's or repre-
   sentative's home, residential office or automobile that is solely limited to conducting the activities protected by 
   P.L.86-272 
•  Licensing of intangible rights for use in Wisconsin

- 3 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• The sale of other than tangible personal property such as real estate, services, and intangibles in Wisconsin
• The performance of services in Wisconsin by employees or representatives, the services of which are unrelated
to the sale of tangible personal property
• Engaging in substantial activities that help to establish and maintain a market in Wisconsin
• Regularly soliciting business from potential customers in Wisconsin, except where protected by P.L.86-272
• Regularly selling products or services of any kind or nature to customers in Wisconsin that receive the product
or service in Wisconsin, except where protected by federal P.L.86-272
• Regularly performing services outside Wisconsin for which the benefits are received in Wisconsin
• Regularly engaging in transactions with customers in Wisconsin that involve intangible property and result in
receipts flowing to the corporation from within Wisconsin
• Issuing credit, debit, or travel and entertainment cards to customers in Wisconsin
• Holding loans secured by real or tangible personal property located in Wisconsin
• Owning, directly or indirectly, a general or limited partnership interest in a partnership that does business in
Wisconsin, regardless of the percentage of ownership
• Owning, directly or indirectly, an interest in a limited liability company treated as a partnership that does business
in Wisconsin, regardless of the percentage of ownership
In the list above, “regular" and “regularly" mean 15 or more days of activity. Fifteen days of activity means one person
for 15 days or 15 persons for one day, or any combination of persons and days that results in at least 15 person-days
of activity. “Days of activity” include any day, or portion thereof, upon which business activity took place. “Days of
activity” do not include travel days, holidays, or weekends, unless business activities were conducted on those days.

IMPORTANT: For combined groups, nexus is determined for the group as a whole. Under sec. 71.255(5),
Wis. Stats., if one member of a combined group is doing business in Wisconsin that relates to the combined group’s
common unitary business, all members of the combined group are considered to be doing business in Wisconsin.
For corporations selling tangible personal property, P.L.86-272 may prohibit Wisconsin taxation in some cases. There
are also specific statutory exemptions from nexus. See sec. Tax 2.82, Wisconsin Administrative Code, for more
information about P.L.86-272 and what creates nexus. See sec. 71.23(3), Wis. Stats., for the specific statutory
exemptions that may apply.

Entities Not Required to File

The following entities are not required to file a Wisconsin franchise or income tax return or be included in a combined
return:
• Single-owner entities that are disregarded under IRC section 7701 (Instead, the owner of the disregarded entity
must file a Wisconsin franchise or income tax return if otherwise required.)
• “Exempt entities,” except those that have income described in a. through c.:
a. Unrelated business taxable income as defined in IRC section 512
b. Income derived from a health maintenance organization (HMO) as defined in sec. 609.01(2), Wis. Stats., or a
limited service health organization (LSHO) as defined in sec. 609.01(3), Wis. Stats., or
c. Income realized from the sale of and subsequent sale or redemption of lottery prizes if the winning tickets were
originally bought in Wisconsin
• Corporations that are completely inactive in and outside Wisconsin and have filed Form 4H
• Credit unions that don’t act as a public depository for state or local government funds and have filed Form CU

Exempt Entities

Exempt entities are described in secs. 71.26(1) and 71.45(1), Wis. Stats. Exempt entities include the following:
• Insurers exempt from federal income taxation under IRC section 501(c)(15)
• Town mutual insurers organized under Chapter 612, Wis. Stats.
• Foreign insurers
• Domestic insurers engaged exclusively in life insurance business

IC-506 (R. 12-24) 3

- 4 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• Domestic insurers transacting mortgage guaranty insurance business as defined in Wisconsin Administrative
• Code section Insurance 6.75(2)(i)
• Some cooperatives
• Religious, scientific, educational, benevolent, or other corporations or associations of individuals not organized
or conducted for profit

Franchise or Income Tax

Corporations may be subject to either franchise or income tax.
Franchise tax applies to:
• All domestic corporations (those organized under Wisconsin law), and
• Foreign corporations (those not organized under Wisconsin law) doing business in Wisconsin or buying or selling
lottery prizes if the winning tickets were originally bought in Wisconsin, except where taxation is exempted by
statute or barred by federal law.
The tax rate is 7.9%. Income from obligations of the United States government and its instrumentalities is included in
income under the franchise tax law.
Income tax applies only to foreign corporations which are not subject to the franchise tax and which own property in
Wisconsin or whose business in Wisconsin is exclusively in foreign or interstate commerce. The tax rate is 7.9%.
Income from obligations of the United States government and its instrumentalities is not included in income under the
income tax law.

Economic Development Surcharge

Corporations may also be subject to the economic development surcharge. The economic development surcharge
is 3% of the corporation’s franchise or income tax, before applying credits. The minimum economic development
surcharge is $25, and the maximum is $9,800.
A corporation is subject to the economic development surcharge if it has gross receipts from all activities of $4 million
or more during the taxable year. See sec. Tax 2.32, Wisconsin Administrative Code and the instructions for Form 6,
Part VI, line 6 for the definition of “Gross Receipts from All Activities".
In a combined group, the economic development surcharge is determined for each company individually based on
its own gross receipts from all activities and its share of the gross tax reported on Form 6, Part III, line 9. If one
member of the combined group has nexus in Wisconsin, all members of the combined group have nexus in Wiscon-
sin.
However, the economic development surcharge doesn’t apply to:

• Domestic corporations that don’t have any business activities in Wisconsin,
• Foreign corporations that don’t have nexus with Wisconsin; however, if one member of the combined group has
nexus in Wisconsin, all combined group members have nexus in Wisconsin, or
• Nuclear decommissioning trust funds.
For more information on the economic development surcharge, refer to the instructions for Form 6, Part III, line 11.
Also refer to Publication 400, Wisconsin’s Economic Development Surcharge. This publication is on the Department
of Revenue’s web site at: https://revenue.wi.gov/Pages/HTML/taxpubs.aspx#other

Separate Return or Combined Return

Use this section to determine if a corporation must be included in a combined return (Form 6) or must file separately
(Form 4). If the corporation must file separately, see the Form 4 Instructions for Non-Combined Returns.

IC-506 (R. 12-24) 4

- 5 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Combined Returns and Groups in General

If a corporation is in a combined group, it should not file a non-combined Form 4, instead, one corporation in the
group, called the “designated agent,” files Form 6 on a combined basis for the group as a whole.
The following cannot be included in a combined return. If these entities are otherwise required to file, a separate
Wisconsin return is needed.
• Tax-option (S) corporations,
• Real estate investment trusts (REITs),
• Regulated investment companies (RICs),
• Real estate mortgage investment conduits (REMICs)
• Financial asset securitization investment trusts (FASITs)
A corporation is in a combined group if it meets all of the following three tests:
• The corporation is in a commonly controlled group
• The corporation is engaged in a unitary business with other corporations in the commonly controlled group,
and
• The corporation is not excluded from the combined group under the water’s edge rules
Each of the three tests is discussed below:

Test 1: Commonly Controlled Group

Section 71.255(1)(c), Wis. Stats., and sec. Tax 2.61(3), Wisconsin Administrative Code, describe when a “commonly
controlled group” exists. To summarize those provisions, a “commonly controlled group” means any or a combination
of the following arrangements, if the “50% test” described below is met:
• A parent-subsidiary chain of corporations
• Corporations with a common owner
• Corporations owned or controlled by members of the same family
• Corporations that are “stapled entities”
50% Test. In any commonly controlled group, there must be common ownership of stock representing more than
50% of the voting power. A corporation owns stock representing more than 50% of voting power if it owns or controls
more than 50% of all classes of stock entitled to vote. See sec. Tax 2.61(3)(d), Wisconsin Administrative Code, for
other rules that apply in determining voting power.
The common ownership may be either direct or indirect. The stock attribution rules of IRC section 318 apply to the
50% test. See sec. Tax 2.61(3)(a), Wisconsin Administrative Code, for examples.
Following is a brief description of each type of commonly controlled group:
Parent-Subsidiary Chain. In this type of group, a parent corporation directly or indirectly owns stock representing
more than 50% of the voting power of one or more corporations or chains of corporations in the group.
Corporations with Common Owner. In this type of group, a common owner directly or indirectly owns stock rep-
resenting more than 50% of the voting power of the corporations in the group. The common owner may or may not
be a corporation.
Corporations Owned or Controlled by Family Members. In this type of group, stock representing more than 50%
of the voting power in each corporation is directly owned by, or for the benefit of, members of the same family, as
determined by the third degree of kinship under sec. 990.001(16), Wis. Stats. Using the third degree of kinship, an
individual is considered to be in the same family with their:
• Parents • Grandparents • Great-grandparents
• Children • Grandchildren • Great-grandchildren
• Siblings • Nieces and nephews • Aunts and uncles

IC-506 (R. 12-24) 5

- 6 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Stapled Entities. In this type of group, there is an arrangement where stock representing more the 50% of the voting
power of each corporation cannot be separately transferred, even if there is not actual common ownership of the
stock. If a group of corporations would be considered “stapled entities” under section 269B of the IRC, without regard
to whether the corporations are foreign or domestic, then the corporations are in a commonly controlled group. See
sec. Tax 2.61(3)(d), Wisconsin Administrative Code, for details.

Test 2: Unitary Business

In general, a “unitary business” is a group of commonly controlled companies, divisions, or branches that operates
as a unit. The operations are integrated, and each company, division, or branch is dependent upon or contributory
to the business operations as a whole. However, it isn’t necessary that each component of the business contribute
to all the other components.
Controlled Group Election. A commonly controlled group may elect to forego the unitary business test. The election
treats the whole group as if it is in the same unitary business, regardless of whether the companies are actually
engaged in a unitary business.
If the group makes the controlled group election, the election is generally binding on the combined group and the
department for a ten-year period, unless the group no longer has a filing requirement. For information on the con-
trolled group election, see the specific line instructions that follow.
How to Identify a “Unitary Business.” If the commonly controlled group does not make the controlled group elec-
tion, it uses the definition in sec. 71.255(1)(n), Wis. Stats., and guidance provided in sec. Tax 2.62, Wisconsin Ad-
ministrative Code, to determine if corporations in the commonly controlled group are engaged in the same unitary
business. The law provides the following:
• Commonly controlled entities are engaged in a unitary business if their activities generate a synergy and mutual
benefit that produces a sharing or exchange of value among them and a significant flow of value to the separate
parts.
• Commonly controlled entities are presumed to be a unitary business if the entities have unity of operation and
use.
The Wisconsin Statutes and Administrative Code provide further explanation and examples of the “sharing, ex-
change, and flow of value” concept and the “unity of ownership, operation and use” concept, summarized as follows:
Sharing, Exchange, and Flow of Value. Commonly controlled corporations are engaged in a unitary business if
any of the following are true:
• The corporations contribute or are expected to contribute in a nontrivial way to each other’s profitability.
• The corporations are dependent on one another for achieving one or more nontrivial business objectives.
• The corporations taken as a group offer one or more corporations in the group some economies of scale or
economies of scope.
To illustrate this concept, the following activities between commonly controlled corporations indicate that they are
engaged in the same unitary business:
• Assisting in acquisition of assets
• Assisting with filling personnel needs
• Lending funds, guaranteeing loans, or pledging assets
• Common future planning or development of the enterprise
• Providing technical assistance, general operational guidance, or overall operational strategic advice
• Supervising
• Sharing use of trade names, patents, or other intellectual property
Unity of Operation and Use. Commonly controlled corporations are also engaged in a unitary business if they have
both unity of operation and unity of use.
Unity of operation means there is functional integration among the corporations, evidenced by shared support func-
tions such as:
• Centralized purchasing, marketing, advertising, accounting, or research and development

IC-506 (R. 12-24) 6

- 7 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• Intercorporate sales or leases, including equipment and real estate
• Intercorporate services, including administrative, data management, computer support, employee benefits, hu-
man resources, insurance, tax compliance, legal, financial, and cash management services
• Intercorporate debts
• Intercorporate use of proprietary materials, including trade names, trademarks, service marks, patents, copy-
rights, and trade secrets
Unity of use is demonstrated by centralized management or use of centralized policies. Factors indicating unity of
use include:
• Centralized executive force
• Interlocking directorates or corporate officers
• Intercompany employee transfers
• Common employee and executive training programs
• Common hiring and personnel policies
• Common recruiting programs
• Common employee handbooks
• Common employee benefit programs
Passive Holding Companies in Unitary Business. If a commonly controlled group includes a passive holding
company that holds intangible assets that are used by other companies of the group in a unitary business, that
holding company is deemed to be engaged in the unitary business, even if its activities are primarily passive.
If a passive parent holding company directly or indirectly controls one or more operating company subsidiaries en-
gaged in a unitary business, that passive parent holding company is also engaged in the unitary business, even if
its activities are primarily passive.
Presumptions to Simplify Determination. In order to simplify the determination of whether a unitary business
exists, sec. Tax 2.62(6), Wisconsin Administrative Code, provides that a group of commonly controlled corporations
is presumed to be engaged in a unitary business if any of the following are true:
• The group’s activities are all in the same general line of business.
• The members of the group are engaged in different steps of a vertically structured enterprise.
• There is strong central management coupled with the existence of centralized departments or affiliates for such
functions as financing, advertising, R&D, or purchasing.
Also, if a corporation forms a new corporation, the forming corporation and new corporation are presumed to be
engaged in a unitary business with one another from the date of formation.
These presumptions may be rebutted by the taxpayer or by the department based on the specific facts and circum-
stances.

Test 3: Water’s Edge

The water's edge test determines how foreign sourced income is reported on a combined return.
If 80% or more of a corporation's worldwide gross income is “active foreign business income” the corporation is on
the foreign side of the water's edge. If less than 80% of a corporation's worldwide gross income is “active foreign
business income” the corporation is on the domestic side of the water's edge.
Active foreign soured business income is defined in subchapter N of the IRC, including income of a subsidiary
corporation, and attributable to the active conduct of a trade or business in a foreign country or in a U.S. possession.
A corporation is considered a subsidiary if the parent corporation owns, directly or indirectly, stock with at least 50
percent of the total voting power of the corporation and the stock has a value equal to at least 50 percent of the total
value of the stock of the corporation. The water’s edge rules are described in detail later in the Form 6 instructions.

IC-506 (R. 12-24) 7

- 8 -

Enlarge image

                                    2024 Form 6 Instructions for Combined Returns 
 
 SUMMARY: A corporation must file in a combined return if all the following are true: 
 1. The corporation is in a commonly controlled group,  
 2. The corporation is  engaged in a unitary business  with  one or more other corporations in that commonly 
    controlled group or the group makes the controlled group election, and 
 3. The corporation is not excluded from the combined group under the water’s edge rules. 
                                                                                                                       
General Franchise or Income Tax Return Instruction 

 Who is the “Designated Agent?” 

Every combined group must appoint a corporation to be the “designated agent” for the group. The designated agent 
acts on behalf of all members of the combined group for matters that relate to the combined return, such as filing 
the return, making estimated payments, sending, and receiving correspondence relating to the combined return, and 
similar duties. 
Note: The designated agent must be included in one of the member columns on Parts I – VI.  

Any corporation in the group can be the designated agent, as long as the designated agent’s taxable year is the 
same as the combined group’s taxable year. The department will consider the company filing the combined group’s 
first combined return to be the designated agent. That company stays the group’s designated agent until either it 
leaves the group, ceases to exist, notifies the department another designated agent has been appointed or the 
combined group is acquired by another combined group. 
See sec. Tax 2.65, Wisconsin Administrative Code, for rules that relate to changing the designated agent and the 
scope and limitations of the designated agent’s responsibilities.  

When and Where to File 

Generally, a combined group must file its Wisconsin franchise or income tax return by the 15th day of the 4th month 
following the close of its taxable year. However, combined groups with a fiscal year ending June 30 are due the 15th 
day of the 3rd month after the close of the taxable year (September 15).  If any due date falls on a Saturday, Sunday, 
or legal holiday, use the next business day.  
The fee for filing a late return after the extension date is $150.  
Short Period Returns. If a combined group member has a short period or joins or leaves the combined group during 
the taxable year, but the combined group itself does not have a short period, the designated agent need not file a 
short period combined return. Instead, the designated agent includes that corporation’s information for the period it 
was a member of the group in the full year combined return. The due date of the combined return is based on the 
combined group’s full taxable year. 

 Note: If a member corporation’s taxable year is a short period or the corporation was not a member of the group for 
 the entire taxable year, identify the period included in the combined return, Form 6, Part VI, line 2.  
 
However, if the entire combined group has a short period, the designated agent must file the combined return based 
on the short period, and the combined return is due on or before the federal due date for that short taxable year. 

 Note: Be sure to use the correct year's tax return when filing for a short period. If the tax returns are not yet 
 available, wait until the returns become available and file under extension.  For example, if a taxpayer has a short 
 period from January 1, 2025, through March 31, 2025, the 2025 Form 6 will not be ready by July 15, 2025 (unex-
 tended due date for a March 31 year-end).  Wisconsin law provides for an automatic 7-month extension to file the 
 return, so filing under extension will allow the correct years return to be filed when the 2025 Form 6 is available 
 (typically the middle of November 2025).  Note that an extension does not extend the time to pay a balance due.  
 To avoid interest charges, pay the amount due by the unextended due date.   

Extensions. Wisconsin law provides an automatic extension of 7 months or until the original due date of the corpo-
ration’s corresponding federal return, whichever is later. 

IC-506 (R. 12-24)                                          8

- 9 -

Enlarge image

                                  2024 Form 6 Instructions for Combined Returns 
 
Any extension allowed by the IRS for filing a federal return automatically extends the Wisconsin due date to 30 days 
after the federal extended due date. Neither a copy of the federal extension nor an application for a Wisconsin 
extension needs to be submitted to the department by the original due date of the return. However, a copy of the 
federal extension must be submitted with the Wisconsin return.  
Disaster Relief Extension. If the return is filed under extension because of a federal or state disaster, include a 
statement indicating which disaster extension applies and attach it to the return. More information on disaster areas 
can be found here:  revenue.wi.gov/Pages/FAQS/pcs-extensn.aspx 
CAUTION: An extension for filing the return doesn’t extend the time to pay the franchise or income tax. Interest will 
be charged on the tax not paid by the 15th day of the 4th month (3rd month for fiscal years ending June 30) following 
the close of the combined group’s taxable year. Avoid interest charges during the extension period by paying the tax 
due by that date. 
Filing Methods. Section 2.67(2)(b), Wis. Adm. Code, requires original and amended combined returns to be filed 
electronically unless an approved electronic waiver is received from the department. If an electronic filing waiver 
request was approved, mail a complete copy of the tax return using the correct year's forms. Print the return single 
sided in black ink. Do NOT staple the tax return. 
Tax returns cannot be filed through e-mail or fax. 
For a list of software vendors participating in electronic filing, visit the department’s web page. 
Supplemental schedules not pre-programmed into the electronic filing software may be submitted in one of two 
ways: 
• Submitting them electronically in .pdf format along with the electronically filed return, or 
• Mailing them to the department with a Form W-RA, Required Attachments for Electronic Filing. 
Methods of Providing Federal Return. For combined group members that also file in a federal consolidated return, 
there are three alternative ways a combined group can meet the requirement to provide the complete federal return 
of each member of the group. The alternatives are: 
• A copy of the federal consolidated return, including all supporting forms, schedules, and statements, as submit-
  ted to the IRS. 
• Pro forma federal returns prepared separately for each member of the combined group included in the federal 
  consolidated return, including all supporting forms and schedules prepared separately for each member. 
A spreadsheet showing the line-by-line computation of taxable income of each member of the combined group 
included in the federal consolidated return, plus the supporting forms, schedules, and statements filed with the IRS 
pertaining to each member, including balance sheets, a reconciliation of income per books with income per return, 
and a reconciliation of retained earnings, to the extent the member was required to submit these items to the IRS.  

Period Covered by Return 

If two or more members of the combined group file in a federal consolidated return, the combined group's taxable 
year is the taxable year of that federal consolidated return. If no federal consolidated return applies or there is more 
than one federal consolidated return, the combined group's taxable year is the taxable year of the designated agent.  
The designated agent's taxable year is required to be the same as the combined group's taxable year. 
Conformity with Period for Federal Return 
Each combined group member's taxable year must be the same as the federal return. Federal rules require: 
• The taxable year ends on the last day of the month unless a stock ownership change requires otherwise.  
• A taxable year may not cover a period of more than 12 calendar months unless a 52-53 week election is made. 
Any change in accounting period made for federal purposes must also be made for Wisconsin purposes. For the 
first taxable year for which the change applies, file with the Wisconsin return a copy of the IRS’s notice of approval 
of accounting period change if such approval is required or an explanation of the change if the IRS’s approval isn’t 
required. 
 
IC-506 (R. 12-24)                                        9

- 10 -

Enlarge image

                            2024 Form 6 Instructions for Combined Returns 
 
Part-year Members of a Combined Group  
If a corporation becomes a member of a combined group or ceases to be a member of a combined group after the 
beginning of the taxable year of the combined group, the corporation’s income shall be determined as provided 
under 71.255(3), (4) or (5), Wis. Stats., for the portion of the year in which the corporation was a member of the 
combined group and that income shall be included in the combined report. The income for the remaining short period 
shall be reported on a separate return or separate combined report. 
Members with Different Taxable Years 
If a member of a combined group has a different taxable year than the designated agent, the designated agent must 
use one of two methods to convert that member’s taxable year to the combined group’s taxable year:  
• Prepare a separate income statement for the member for the months included in the combined group’s taxable 
  year, or 
• Use the amounts for the member’s taxable year that ends during the combined group’s taxable year.  
• Example: Corporation A becomes a member of Combined Group B on April 1and has a tax year ending De-
  cember 31. Combined Group B has a fiscal year ending March 31. Combined Group B may elect one of the 
  following ways to determine the portion of Corporation A's income in its 2024 (fiscal year end March 31, 2025) 
  combined return: 
• Convert Corporation A's records to Combined Group B's tax year by filing a separate short-year return for Cor-
  poration A covering January 1, 2024, through March 31, 2024. Prepare a separate income statement and include 
  Corporation A's income for the period April 1, 2024, through March 31, 2025, in Combined Group B's 2024 
  combined return (fiscal year end March 31, 2025). 
• Include all of the income from Corporation A's year that ends during Combined Group B's taxable year. Com-
  bined Group B's 2024 combined return (fiscal year end March 31, 2025) would contain Corporation A's income 
  from the period January 1, 2024, through December 31, 2024. Once Combined Group B elects to use this 
  method, it is irrevocable except upon written approval by the department. 

 Note: If a member is on a different taxable year than the combined group, identify its taxable year end on Form 6, 
 Part VI, line 2. 

Accounting Methods and Elections 

Generally, the accounting method must be the same as used to calculate federal net income. However, if the federal 
method isn’t authorized under the IRC in effect for Wisconsin, use a method authorized under the IRC in effect for 
Wisconsin. 
Situations Where Installment Method Not Authorized for Wisconsin. A corporation entitled to use the installment 
method of accounting must take the unreported balance of gain on installment obligations into income in the taxable 
year of their distribution, transfer, or acquisition by another person or for the final taxable year for which it files or is 
required to file a Wisconsin franchise or income tax return, whichever year occurs first. 
Change in Accounting Method. A change in accounting method made for federal purposes must also be made for 
Wisconsin purposes, unless the change isn’t authorized under the IRC in effect for Wisconsin. Adjustments required 
federally as a result of a change made while a corporation is subject to Wisconsin taxation must also be made for 
Wisconsin purposes, except in the last year that a corporation is subject to taxation by Wisconsin it must take into 
account all remaining adjustments required. 
For the first taxable year for which the change applies, file with the Wisconsin return either a copy of the application 
for change in accounting method filed with the Internal Revenue Service and copy of the IRS’s consent, if applicable, 
or an explanation of the change if the IRS’s approval isn’t needed.  
Elections. A corporation can’t make different elections for federal and Wisconsin purposes with respect to account-
ing periods and accounting methods, unless the federal method is not permitted under the IRC in effect for Wiscon-
sin. In situations where a corporation has an option under the IRC and the IRS doesn’t consider that option to be a 
method of accounting, a different election may be made for Wisconsin than for federal purposes. If federal law 
specifies the manner or time period in which an election must be made, those requirements also apply for Wisconsin 
purposes. For additional information, see page 8 of Wisconsin Tax Bulletin 214. 
 
IC-506 (R. 12-24)                                   10

- 11 -

Enlarge image

                                   2024 Form 6 Instructions for Combined Returns 
 
Payment of Estimated Tax 

If the total of a combined group’s franchise or income tax and economic development surcharge due is $500 or 
more, generally quarterly estimated tax payments must be made to avoid an interest charge. The designated agent 
must make quarterly estimated tax payments on behalf of all members of the combined group. See sec. Tax 2.66, 
Wisconsin Administrative Code, for details and exceptions. 

 Note: The combined group is generally treated as a single corporation for purposes of determining required esti-
 mated payments and interest. See the instructions to Form U, Underpayment of Estimated Tax by Corporations      , for 
 details.  
Quick Refund. A combined group that overpaid its estimated tax may apply for a refund before filing its tax return if 
its overpayment is (1) at least 10% of the expected Wisconsin tax liability and (2) at least $500. To apply, the desig-
nated agent may file Wisconsin Form 4466W, Corporation or Pass-Through Application for Quick Refund of Over-
payment of Estimated Tax, after the end of the taxable year and before the corporation files its tax return.  
A combined group that has a tax due when filing its tax return as a result of receiving a “quick refund” will be charged 
12% annual interest on the amount of unpaid tax from the date the refund is issued to the earlier of the 15th day of 
the 4th month (3rd month for fiscal years ending June 30) after the close of the taxable year or the date the tax 
liability is paid. Any tax that remains unpaid after the unextended due date of the tax return continues to be subject 
to 18% or 12% annual interest, as appropriate. 
Electronic Funds Transfer Required. Section Tax 1.12, Wisconsin Administrative Code, requires the payment of 
certain taxes by electronic funds transfer (EFT). A combined group must pay its estimated franchise or income taxes 
and economic development surcharge by EFT if its net tax less refundable credits on its prior year return was $1,000 
or more.  
Combined groups not required to pay by EFT may elect to do so. For more information, visit the Department of 
Revenue’s web site at  revenue.wi.gov/Pages/FAQS/pcs-eft.aspx, e-mail      DORBusinessTax@wisconsin.gov       , call 
(608) 264-9918, or write to the EFT Unit, Wisconsin Department of Revenue, PO Box 8949, Madison, WI 53708-
8949. 
If EFT payments are not required, estimated payments can be made using Form Corp-ES, Wisconsin Corporation 
Estimated Tax Voucher. A voucher can be created from the department’s web site at     revenue.wi.gov/html/form-
pub.html. 

Components of Combined Return 

Section Tax  2.67(2)(c), Wisconsin Administrative Code, prescribes the components that a combined return must 
have in order to be considered complete. 
All combined returns must include a copy of the complete federal return for each member of the combined group.  
Other Supporting  Schedules.    The line-by-line instructions  indicate when schedules  are required to support 
amounts reported on the return. In some cases, the schedules must be on specific department-prescribed forms, 
and in other cases taxpayer prepared schedules are accepted. Follow  the line-by-line instructions carefully. See       
Required Attachments later in the instructions.  

Required Disclosures and Information Returns 

Specific disclosure requirements when thresholds under sec. 71.81(1)(e), Wis. Stats., are met. 
Listed Transaction - means any reportable transaction that is the same as, or substantially similar to, a transaction, 
plan, or arrangement specifically identified by the U.S. secretary of the treasury as a listed transaction, for purposes 
of section 6011 of the Internal Revenue Code and that is specifically identified by the U.S. secretary of the treasury 
as a listed transaction on or after the date the transaction occurred. See Disclosure of Reportable Transactions - 
Taxpayer Requirements for more information.  
Reportable Transaction Disclosed by the Corporation – means any transaction, plan, or arrangement, including a 
listed transaction, for which a taxpayer is required to submit information to the department because the taxpayer is 
required to disclose the transaction, plan, or arrangement for federal income tax purposes for the taxable year in 
which the transaction occurred, as provided under U.S. department of treasury regulations  See. Disclosure of Re-
portable Transactions - Taxpayer Requirements for more information. 

IC-506 (R. 12-24)                                      11

- 12 -

Enlarge image

                                 2024 Form 6 Instructions for Combined Returns 
 
For each taxable year a taxpayer has participated in a reportable transaction, the taxpayer shall, 
• Check the "yes" box on Form 6, Part VI, line 27 
• File with the department a copy of any form required by the internal revenue service for disclosing the reportable 
  transaction for federal income tax purposes no later than 60 days after the date for which the taxpayer is required 
  to file the form for federal income tax purposes. 
• A Form 8886, Reportable Transaction Disclosure Statement, can be transmitted with the Form 6. 
Material Advisor –  A material advisor means any person who provides any material aid, assistance, or advice with 
respect to organizing, managing, promoting, selling, implementing, insuring, or carrying out any reportable transac-
tion and who, directly or indirectly, derives gross income from providing such aid, assistance, or advice in an amount 
that exceeds the threshold amount. 
• A material advisor required to file federal Form 8918, Material Advisor Disclosure Statement, must file a copy 
  with the Department of Revenue within 60 days of the date it is required for federal income tax purposes, pro-
  vided that the form relates to a taxpayer that is required to file a Wisconsin franchise or income tax return. 
• Form 8918 is not transmitted with the Form 6. 
• To file this form for Wisconsin purposes, send a paper copy, separate from the Wisconsin return, to the following 
  address along with a list of the names and identification numbers of each Wisconsin taxpayer for whom the 
  advisor provided services to.  
Wisconsin Department of Revenue 
Tax Shelters Program 
PO Box 8906 
Madison, WI 53708-8906  
 
See Disclosure of Reportable Transactions - Material Advisor Requirements for more information.  
 
Other Required Disclosures 
Uncertain Tax Positions – If the Schedule UTP-Uncertain Tax Position Statement, is required for federal purposes, 
include, a copy of the schedule with the Wisconsin tax return and check the "yes" box on Form 6, Part VI, line 26. 
Information Return for Miscellaneous Income   – If a corporation paid $600 or more in rents, royalties, or certain 
nonwage compensation to one or more individuals, the corporation must report the payments on Wisconsin Form 9b, 
Miscellaneous Income,  or  federal Forms 1099  or 1099-NEC instead of Form 9b. For  more  information, see the 
Form 9b instructions.  
Disclosure of Related Entity Expenses –   If the combined group deducts interest, rent, management fees, or in-
tangible expenses paid, accrued, or incurred to a related person or entity, $100,000 or more, Schedule RT, Wiscon-
sin Related Entity Expenses Disclosure Statement, must be filed with the combined return. The Schedule RT in-
structions explain the reporting requirements.  
The $100,000 threshold is determined after considering the effect of the combined group’s Wisconsin apportionment 
percentage. The Schedule RT instructions explain the reporting requirements.  
However, even if Schedule RT is not required to be filed, if the combined group is claiming deductions for interest, 
rent, management fees, or intangible expenses, paid, accrued, or incurred to related entities, the expenses must be 
added back to federal income as a Wisconsin addition modification. To the extent the expenses meet the tests for 
deductibility, they qualify as a subtraction modification. See the instructions for Form 6, Part II, lines 2c, 4b, and 4c, 
and Disclosure of Related Entity Expenses on Schedule RT for additional details. 

Internal Revenue Service Adjustments, Amended Returns, and Claims for Refund 

Internal Revenue Service Adjustments. If a corporation’s federal tax return is adjusted by the IRS and the adjust-
ments affect the Wisconsin net tax payable, the amount of a Wisconsin credit, a Wisconsin net business loss car-
ryforward, or a Wisconsin capital loss carryforward, the adjustments are required to be reported to the Department 
of Revenue within 180 days after the adjustments become final by either filing an amended Wisconsin franchise/in-
come tax return or mailing a copy of the final federal audit report. Include a copy of the final federal audit report with 
the electronically filed amended return.  
 
IC-506 (R. 12-24)                                   12

- 13 -

Enlarge image

                                2024 Form 6 Instructions for Combined Returns 
 
Note: Section 2.67(2)(b), Wis. Adm. Code, requires combined corporate tax returns to be filed electronically.  This 
includes amended returns. 
To submit a federal audit report without an amended return, mail it to the following address: 
Audit Bureau  
Wisconsin Department of Revenue, Mail Stop 3-107  
PO Box 8906, Madison, WI 53708-8906.  
Amended Returns. After a complete, original tax return has been filed, an amended return may be filed to correct 
an originally filed or previously amended return, claim for refund, or an office or field audit adjustment. 
If a federal amended return reflects changes affecting the Wisconsin net tax payable, the amount of a Wisconsin 
credit, a Wisconsin net business loss carryforward, or a Wisconsin capital loss carryforward, an amended Wisconsin 
return must be filed with the Department of Revenue within 180 days after filing the amended federal return. 
• When submitting an amended Wisconsin return, put a check mark on line D1 on the front of the return, complete 
  the return, and include Schedule AR explaining the changes made. Show computations in detail, including any 
  applicable supplemental forms or schedules. Also show how the refund or additional amount owed was com-
  puted. Where applicable, the line-by-line instructions in these instructions provide specific instructions for how 
  to compute the amounts on an amended return.  
• Do not include a copy of the original return with the amended return.        
• Don’t include amended returns with other tax returns being filed. 
Note: Section 2.67(2)(b), Wis. Adm. Code, requires combined corporate tax returns to be filed electronically unless 
an approved electronic waiver is received from the department. This includes amended returns. See Filing Methods.  
If an electronic filing waiver was approved, send amended returns to:  
Wisconsin Department of Revenue 
PO Box 8908 
Madison, WI 53708-8908  
• If an electronic filing waiver was approved and the return is filed on paper, a complete return including all Wis-
  consin and federal forms and schedules must be submitted. 
• Combined groups of more than 3 members need to include a complete set of pages 3-14 for each member 
  group of 3 (i.e., if there are 9 members in the group, 3 sets of pages 3-14 are required). 
Claims for Refund. A claim for refund must be filed within 4 years of the unextended due date of the return. How-
ever, a claim for refund to recover all or part of any tax or credit paid as a result of an office or field audit must be 
filed within 4 years after such an assessment. That assessment must have been paid and must not have been 
protested by filing a petition for redetermination (appeal). See sec. Tax 2.12, Wisconsin Administrative Code, for 
more information on claims for refund and other amended returns. 

Final Return 

If the combined group dissolved during the table year, put a check mark on line D3 on page 1 of Form 6.    
If a combined group member liquidated during the taxable year, put a check mark on line 18, Part VI of Form 6. 
Enter the date of liquidation as the end of the period included in the combined return on Form 6, Part VI, line 2. 
Submit a copy of the plan of liquidation and a copy of federal Form 966 with the combined return.  
A final return is due on or before the federal due date. In most cases, this is the 15th day of the 4th month after the 
date the corporation dissolved; however, combined groups with a fiscal year ending June 30 are due the 15th day 
of the 3rd month after the close of the taxable year. The tax is payable by the 15th day of the 4th month after the 
date of dissolution, except that taxable years beginning in April are due the 15th day of the 3rd month. However, 
since the taxable year is determined for the combined group as a whole, the due date of that member’s final return 
is based on the due date of the combined return. See Short Period Returns, under When and Where to File, for 
details.  
Note: checking the final return box will not close all accounts with the department; only the corporation account will 
close. 

IC-506 (R. 12-24)                                    13

- 14 -

Enlarge image

                                 2024 Form 6 Instructions for Combined Returns 
 
Penalties for Not Filing or Filing Incorrect Returns 

If a required franchise or income tax return is not filed or it is filed incorrectly due to negligence or fraud, interest and 
penalties may be assessed.  The interest rate on delinquent taxes is 18% per year. Civil penalties may be as much 
as 100% of the amount of tax not reported on the return. Criminal penalties for filing a false return include a fine of 
up to $10,000 and imprisonment.  
Further, if reportable transactions are not disclosed, the penalties described in sec. 71.81, Wis. Stats. May be as-
sessed, including a $30,000 penalty for failure to disclose a listed transaction. 

Conformity with Internal Revenue Code and Exceptions 

The Wisconsin income and franchise tax law is based on the federal Internal Revenue Code (IRC). The IRC generally 
applies for Wisconsin purposes at the same time as for federal purposes.  For taxable years beginning on or after 
January 1, 2024, Wisconsin's definition of the IRC is the IRC as of December 31, 2022 with the following exceptions 
listed below.  

Provisions of the Internal Revenue Code Adopted by Wisconsin 

Changes made by the following public laws apply for Wisconsin purposes for taxable years beginning after Decem-
ber 31, 2010: 
•  Section 1201 of P.L. 108-173, relating to health savings accounts. 
•  Section 307 of P.L. 109-432, relating to the exclusion from gross income of a one-time distribution from individual 
   retirement accounts to fund health savings accounts. 
Changes made by the following public laws apply for Wisconsin purposes for taxable years beginning after Decem-
ber 31, 2022: 
•  Sections 5001, 5002, 5005, 9623, 9624, and 9672 of P.L. 117-2 
   o  Section 5001, relating to the addition of certain nonprofit entities and internet publishing organizations to the 
    list of eligible entities to receive a paycheck protection program loan. 
   o  Section 5002, relating to additional appropriations for targeted economic injury disaster loan advances. 
   o  Section 5005, relating to additional appropriations for shuttered venue operator grants and a reduction in 
    the amount of a paycheck protection program loans received. 
   o  Section 9623, relating to allowing a married individual who files as married filing separate and lives apart 
    from their spouse for the last 6 months of the year or has a divorce or separation instrument with the other 
    spouse by the end of the tax year to claim the earned income credit. 
   o  Section 9624, relating to permanently raising the investment income limit to $10,000, and allowing adjust-
    ments for inflation in subsequent years for purposes of claiming the earned income credit.  
   o  Section 9672, relating to targeted economic injury disaster loan advances received under sec. 331 of Divi-
    sion N of P.L. 116-260 not being included in gross income, allowing deductions, not reducing tax attributes, 
    and allowing a basis increase.  For partnerships and S corporations, any amount forgiven are treated as 
    tax-exempt for purposes of sec. 705 and 1366, IRC. 
 • Section 2 of P.L. 117-6, relating to the extension of paycheck protection program loan funding to June 30, 2021. 
 • The following sections of Division H of P.L. 117-58: 
   o  Section 80401, relating to the addition of qualified broadband projects to the list of federally exempt facility 
    bonds. 
   o  Section 80402, relating to the addition of qualified carbon dioxide capture facilities to the list of federally 
    exempt facility bonds. 
   o  Section 80601, relating to including certain contributions received by a regulated public utility which provides 
    water or sewerage disposal services in the definition of a "contribution to the capital of the taxpayer" for 
    purposes of excluding the contribution from gross income of a corporation. 
     
IC-506 (R. 12-24)                                    14

- 15 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Provisions of the Internal Revenue Code Not Adopted by Wisconsin:

• Sections 1, 3, 4, and 5 of P.L. 106-519, which repealed foreign sales corporation provisions and replaced with
extraterritorial income provisions.
• Sections 101, 102, and 422 of P.L. 108-357, which repealed the exclusion for extraterritorial income, domestic
production activities deduction, and the creation of sec. 965 – incentives to reinvest foreign earnings in the U.S.
• Sections 1310 and 1351 of P.L. 109-58, which provides for the modification to special rules for nuclear decom-
missioning costs, repeal of the limitation on contract research expenses paid so small businesses, universities,
and federal laboratories.
• Section 11146 of P.L. 109-59, the tax treatment of state ownership of railroad real estate investment trust.
• Section 403(q) of P.L. 109-135, which provides incentives to reinvest foreign earnings from controlled foreign
corporations in the U.S.
• Section 513 of P.L.109-222, which repeals foreign sales corporation/extraterritorial income exclusion binding
contract relief.
• Section 104 of P.L. 109-432, which increases the rates of the alternative incremental credit and provides a new
alternative simplified credit.
• Sections 8233 and 8235 of P.L. 110-28, which created a special rule for banks required to change from the
reserve method of accounting in becoming tax-option (S) corporations and the elimination of all earnings and
profits attributable to pre-1983 years.
• Section 11(e) and (g) of P.L. 110-172, which provides clerical amendments to research credits for controlled
corporations and common control, and clerical amendments to the FSC Repeal and Extraterritorial Income Ex-
clusion Act of 2000.
• Section 301 of P.L. 110-245, which provides for tax responsibilities of expatriation.
• Section 15351 of P.L. 110-246, limits the amount of farm losses that may offset non-farming business income
to $300,000.
• Section 302 of division A, section 401 of division B, and sections 312, 322, 502(c), 707, and 801 of division C of
P.L. 110-343, which limits executive compensation for employers participating in troubled assets relief program
for the taxable year in which the troubled assets exceed $300,000,000. Caps the domestic production activities
deduction at 6% for oil-related activities. The deduction for income attributable to domestic production activities
in Puerto Rico applies to the first 8 taxable years beginning before January 1, 2010. Tax incentives for invest-
ment in the District of Columbia includes exclusion for gain on sale of an asset held from more than 5 years.
Defines wages for purposes of the domestic production activities deduction. Creates sec. 198A to provide for
expensing of disaster expenses for control of hazardous substances. Specifies treatment of nonqualified de-
ferred compensation plans maintained by foreign corporations.
• Sections 1232, 1251, 1501, and 1502 of division B of P.L. 111-5, which suspends the special rules for original
issue discount on high yield obligations issued during the period 9/1/2008 and 12/31/2009. Provides that no
built-in-gain tax is imposed on a tax-option (S) Corporation for a taxable year beginning in 2009 and 2010 if the
seventh taxable year in the corporation's recognition period preceded such taxable year. Tax-exempt obligations
held by financial institutions, in an amount not to exceed 2 percent of the adjusted basis of the financial institu-
tion's assets, are not taken into account for determining the portion of the financial institutions interest expense
subject to the pro rata interest disallowance rule of sec. 265(b). Modification of the small insurer exception to
tax-exempt interest expense allocation rules for financial institutions.
• Sections 211, 212, 213, 214, and 216 of P.L. 111-226, which adopts a matching rule to prevent the separation
of foreign taxes from the associated foreign income, denies a foreign tax credit for the disqualified portion of any
foreign income tax paid in connection with a covered asset acquisition, provides a separate application of foreign
tax credit limitation to items resourced under treaties, limits the amount of foreign taxes deemed paid with re-
spect to sec. 956 inclusions, treats a foreign corporation as a member of an affiliated group for interest allocation
and apportionment purposes in more than 50% of gross income is effectively connected income and at least
80% of either the vote or value of all outstanding stock is owned directly or indirectly by members of the affiliated
group.
• Section 2122 of P.L. 111-240, which clarifies the income sourcing rules for guarantee fees.
• Sections 754 and 760 of P.L. 111-312, which specifies certain tax incentives for investments in the District of
Columbia and specifies that gross income does not include gain on certain small business stock.

IC-506 (R. 12-24) 15

- 16 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• Sections 104, 318, 322, 323, 326, 327, and 411 of P.L. 112-240, which makes the alternative minimum tax
exemption permanent and indexed for inflation, extends through 2013 the deduction with respect to income
attributable to domestic production activities in Puerto Rico, extends the subpart F exception for active financing
income, extends the look-thru treatment of payments between related controlled foreign corporations under for-
eign personal holding company, extends through 2013 the reduction in tax-option (S) Corporation built-in gains
tax and clarifies treatment of installment sales, provides a 60% exclusion for gain on small business stock ac-
quired before 2019, and extends through 2013 the rules that allow gain certain sales of electric transmission
property to be recognized ratably over 8 taxable years.
• Public Law. 114-7, relating to contributions for relief of slain New York Police Detectives.
• Section 1101 of P.L. 114-74 relating to partnership rules.
• Section 305 of division P of P.L. 114-113, relating to the transportation costs of independent refiners.
• Sections 123, 125-128, 143, 144, 151-153, 165-167, 169-171, 189, 191, 326, and 411 of division Q of P.L. 114-
113:
o Section 123, relating to extension of 15-year straight-line cost recovery for qualified leasehold improve-
ments, qualified restaurant buildings and improvements, and qualified retail improvements.
o Section 125, relating to the extension of treatment of certain dividends of regulated investment companies.
o Section 126, relating to the extension of exclusion of 100 percent of gain on certain small business stock.
o Section 127, relating to the extension of reduction in S-corporation recognition period for built-in gains tax.
o Section 128, relating to the extension of subpart F exception for active financing income.
o Section 143, relating to the extension and modification of bonus depreciation.
o Section 144, relating to the extension of look-thru treatment of payments between related controlled foreign
corporations under foreign personal holding company rules.
o Section 151, relating to the extension and modification of exclusion from gross income of discharge of qual-
ified principal residence indebtedness.
o Section 152, relating to the extension of mortgage insurance premiums treated as qualified residence inter-
est.
o Section 153, relating to the extension of above-the-line deduction for qualified tuition and related expenses.
o Section 165, relating to the extension of classification of certain race horses as 3-year property.
o Section 166, relating to the extension of 7-year recovery period for motorsports entertainment complexes.
o Section 167, relating to the extension and modification of accelerated depreciation for business property on
an Indian reservation.
o Section 169, relating to the extension of special expensing rules for certain film and television productions;
special expensing for live theatrical productions.
o Section 170, relating to the extension of deduction allowable with respect to income attributable to domestic
production activities in Puerto Rico.
o Section 171, relating to the extension and modification of empowerment zone tax incentives.
o Section 189, relating to the extension of special allowance for second generation biofuel plant property.
o Section 191, relating to the extension of special rule for sales or dispositions to implement FERC or State
electric restructuring policy for qualified electric utilities.
o Section 326, relating to the dividends derived from RICs and REITs ineligible for deduction for United States
source portion of dividends from certain foreign corporations.
o Section 411, relating to the partnership audit rules.
• Sections 11011, 11012, 13201 (a) to (e) and (g), 13206, 13221, 13301, 13304 (a), (b), and (d), 13531, 13601,
13801, 14101, 14102, 14103, 14201, 14202, 14211, 14212, 14213, 14214, 14215, 14221, 14222, 14301, 14302,
14304, and 14401 of P.L. 115−97:
o Section 11011, relating to the 20% deduction for domestic qualified business income.
o Section 11012, relating to the limitation on losses for taxpayers other than corporations.
o Section 13201 (a) to (e) and (g), relating to the temporary 100% expensing for certain business assets
(bonus depreciation).
o Section 13206, relating to the amortization of research and experimental expenditures beginning in 2022.

IC-506 (R. 12-24) 16

- 17 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

o Section 13221, relating to special rules for the taxable year of inclusion.
o Section 13301, relating to the 30% taxable income limitation for the deduction of interest.
o Section 13304(a), (b), and (d) relating to the limit on the deduction by employers of fringe benefits (meals,
entertainment, and transportation).
o Section 13531, relating to the limitation on deductions for FDIC premiums.
o Section 13601, relating to the modification of the limitation on excessive employee remuneration.
o Section 13801, relating to the production period for beer, wine, and distilled spirits.
o Section 14101, relating to the deduction for the foreign-source portion of dividends received by domestic
corporations from specified 10% owned foreign corporations.
o Section 14102, relating to the special rules for sale or transfers involving specified 10% owned foreign cor-
porations.
o Section 14103, relating to the treatment of deferred foreign income upon transition to a participation exemp-
tion system of taxation.
o Section 14201, relating to the current year global intangible low-taxed income by U.S. shareholders.
o Section 14202, relating to the deduction for foreign derived intangible income and global intangible low-
taxed income.
o Section 14211, relating to the elimination of the inclusion of foreign base company oil related income.
o Section 14212, relating to the repeal of the inclusion based on withdrawal of previously excluded subpart F
income from qualified investment.
o Section 14213, relating to the modification of stock attribution rules for determining the status as a controlled
foreign corporation.
o Section 14214, relating to the modification of the definition of a U.S. shareholder.
o Section 14215, relating to the elimination of the requirement that a corporation must be controlled for 30
days before the subpart F inclusions apply.
o Section 14221, relating to the limitations on income shifting through intangible property transfers.
o Section 14222, relating to certain related party amounts paid or accrued in hybrid transactions or with hybrid
entities.
o Section 14301, relating to the repeal of section 902 – indirect foreign tax credits, and determination of the
deemed paid credit for subpart F inclusions under sec. 960 on a current year basis.
o Section 14302, relating to the separate foreign tax credit limitation basket for foreign branch income.
o Section 14304, relating to the election to increase the percentage of domestic taxable income offset by the
overall domestic loss treated as foreign source.
o Section 14401, relating to the base erosion anti-abuse tax.
• Sections 40304, 40305, 40306, and 40412 of P.L. 115-123:
o Section 40304, relating to the extension of classification of certain race horses as 3-year property.
o Section 40305, relating to the extension of 7-year recovery period for motor-sports entertainment complexes.
o Section 40306, relating to the extension of accelerated depreciation for business property on an Indian res-
ervation.
o Section 40412, relating to the extension of special allowance for second generation biofuel plant property.
• Section 101 (c) of division T of P.L. 115-141, relating to the application of section 199 to certain qualified pay-
ments paid after 2017 for payments received by a patron from a specified agricultural or horticultural cooperative
for qualified production activities income.
• Sections 101 (d) and (e), 102, 201 to 207, 301, 302, and 401 (a) (47) and (195), (b) (13), (17), (22) and (30),
and (d) (1) (D) (v), (vi), and (xiii) and (xvii) (II) of division U of P.L. 115-141:
o Sections 101 (d) and (e) and 102, relating to technical corrections to bonus depreciation, alternative mini-
mum tax requirements for qualified Indian reservation property, and qualified production activities income
made by the Protecting Americans from Tax Hikes Act of 2015 and the Consolidated Appropriations Act,
2016.
o Sections 201 to 207 relating to partnership audit rules.
o Sections 301 and 302, relating to amendments to regulatory requirements for partnership returns and the

IC-506 (R. 12-24) 17

- 18 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

definition of qualified small power production facilities made by the Bipartisan Budget Act of 2015 and the
Energy Policy Act of 2005.
o Section 401 (a) (47) and (195), (b) (13), (17), (22) and (30), and (d) (1) (D) (v), (vi), and (xiii) and (xvii) (II),
relating to clerical corrections and deadwood-related provisions to the following: exempt facility bonds, tax-
exempt enterprise zone facility bonds, the special allowance for qualified disaster assistance property, re-
ducing the dividends received deduction where portfolio stock is debt financed, exemption from tax on cor-
porations, certain trusts, etc., requirements of domestic international sales corporations, dividends received
by corporations, rules applied to deductions for dividends received, the foreign tax credit, and dividends
received by corporations.
• Sections 104, 114, 115, 116, 130, and 145 of division Q of P.L. 116-94.
o Section 104, relating to the deduction of qualified tuition and related expenses.
o Section 114, relating to the classification of certain racehorses as 3-year property.
o Section 115, relating to the 7-year recovery period for motorsports entertainment complexes.
o Section 116, relating to the accelerated depreciation for business property on Indian reservations.
o Section 130, relating to special allowance for second generation biofuel plant property.
o Section 145, relating to look-thru rule for related controlled foreign corporations.
• Sections 2304 and 2306 of P.L. 116-136:
o Section 2304, relating to the modification of limitations on losses for taxpayers other than corporations.
o Section 2306, relating to the modifications of limitation on business interest.
• Sections 111, 114, 115, 116, 118 (a) and (d), 133, 137, 138, and 210 of division EE of P.L. 116-260.
o Section 111, relating to the look-thru rule for related controlled foreign corporations.
o Section 114, relating to the exclusion from gross income of discharge of qualified principal residence indebt-
edness.
o Section 115, relating to the 7-year recovery period for motorsports entertainment complexes.
o Section 116, relating to the expensing rules for certain productions.
o Section 118 (a) and (d), relating to empowerment zone tax incentives.
o Section 133, relating to the treatment of mortgage insurance premiums as qualified residence interest.
o Section 137, relating to the classification of certain racehorses as 3-year property.
o Section 138, relating to the accelerated depreciation for business property on Indian reservations.
o Section 210, relating to temporary allowance of full deduction for business meals.
• Sections 5003, 9041, 9673, 9675, and 9708 of P.L. 117-2.
o Section 5003, relating to additional restaurant revitalization grant funds.
o Section 9041, relating to the excess business loss limitation extension for noncorporate taxpayers to De-
cember 31, 2026
o Section 9673, relating to restaurant revitalization grants not being included in gross income and deductions
allowed.
o Section 9675, relating to the exclusion from income for most student loans discharged after December 31,
2020, and before January 1, 2026.
o Section 9708, relating to the expanded definition of "covered employee" for publicly held corporations de-
ducting excessive employee remuneration.
• Section 13903(b) of P.L. 117-169, relating to the extension of the excess business loss limitation for
noncorporate taxpayers through December 31, 2028.

Other Exceptions to Internal Revenue Code

The following federal provisions in effect as of December 31, 2022, are specifically excluded for Wisconsin franchise
and income tax purposes:

Depreciation and Bonus Depreciation

For taxable years beginning on or after January 1, 2014, for purposes of computing depreciation, depletion, and

IC-506 (R. 12-24) 18

- 19 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

amortization, the IRC means the federal IRC in effect on January 1, 2014.
The provision that property required to be depreciated for taxable year 1986 under the IRC as amended to December
31, 1980, to continue to be depreciated under the IRC as amended to December 31, 1980, is limited to taxable years
beginning before January 1, 2014.
Bonus Depreciation
Wisconsin has not adopted federal bonus depreciation provisions . For Wisconsin purposes, depreciation, depletion,
and amortization is computed based on the Internal Revenue Code in effect on January 1, 2014. Bonus depreciation
was not in effect on January 1, 2014.

Section 179 Expense

For taxable years beginning on or after January 1, 2014, sections 179,179A 179B, 179C, 179D, , and 179E of the
IRC , related to expensing of depreciable business assets, apply for Wisconsin tax purposes. "Internal Revenue
Code" means the federal IRC in effect for the year in which the property is placed in service.
For combined groups, the section 179 expense limitation applies to the group as a whole, in the same way it would
apply to a federal controlled group as provided in section 179(d)(6), IRC.

Capital Losses

Wisconsin generally follows the capital loss limitations and carryovers provided under the IRC for corporations. If a
corporation has a net capital loss, the loss must be carried to other taxable years and deducted from capital gains
in those years, as provided in section 1212, IRC. However, for Wisconsin purposes, a corporation can’t carry back
a loss to taxable years before 1987. Losses that can’t be carried back may be carried forward 5 years.

Limitations on Certain Federal Deductions

Federal deduction limitations for Wisconsin purposes may need to be recomputed if the federal taxable income for
federal purposes differs from the federal taxable income determined under the IRC in effect for Wisconsin. Reasons
why the federal taxable income for federal purposes may differ from the federal taxable income for Wisconsin pur-
poses include:
• A provision of the IRC is excluded from the definition of IRC in effect for Wisconsin under sec. 71.22(4), Wis.
Stats.
• Different elections under the IRC are made for federal and Wisconsin purposes. For additional information, see
page 8 of Wisconsin Tax Bulletin 214.
The deduction limitations are applied in computing federal taxable income before the Wisconsin modifications pre-
scribed in secs. 71.26(2) and (3), and 71.30, Wis. Stats. Deduction limitations are not recomputed as a result of
making Wisconsin modifications.
Also see Section 179 and Depreciation Adjustments for Wisconsin Common Questions.

Federal Consolidated Return Regulations

In general, Wisconsin does not follow sections 1501 to 1505,1551 1552, 1563, , and 1564 of the IRC, relating to
consolidated returns. However, for combined groups, Wisconsin applies certain regulations under section 1502, IRC,
similarly to how they would apply to consolidated groups for federal purposes. See sec. Tax 2.61(6), Wisconsin
Administrative Code for details.

Differences Between Federal and Wisconsin Basis of Assets

Assets of Previously Nontaxable Corporations. For the first year a corporation is taxable in Wisconsin, the basis
of its assets is its federal basis.

General Instructions for Apportionment

IC-506 (R. 12-24) 19

- 20 -

Enlarge image

                                2024 Form 6 Instructions for Combined Returns 
 
Who Must Use Apportionment 
A corporation engaged in a unitary business in and outside Wisconsin or a combined group engaged in business in 
and outside Wisconsin must report a portion of its total net income to Wisconsin using the apportionment method, 
unless the department gives permission to use separate accounting.  
To use the apportionment method, a corporation or combined group must have business activity sufficient to create 
nexus in Wisconsin and at least one other state or foreign country. “Nexus” means that a corporation’s business 
activity is of such a degree that the state or foreign country has jurisdiction to impose an income tax or franchise tax 
measured by net income.  
Wisconsin’s Administrative Code provides more detailed information about when apportionment is required. The fol-
lowing sections may be helpful: 
• Tax 2.39, Apportionment Method 
• Tax 2.62, Unitary Business 
• Tax 2.82, Nexus 
Apportionment Method 
Under the apportionment method, a corporation or combined group shows its income and deductions attributable the 
unitary business and assigns a part to Wisconsin according to an apportionment percentage. In a combined group, 
the apportionment percentage of the combined group is determined by each combined group member’s apportion-
ment factor numerator divided by the sum of all group members' apportionment factor denominator.  
For most corporations required to use apportionment, the apportionment factor numerator is Wisconsin sales, and 
the denominator is total company sales. This is known as the “single sales factor” method. Corporations that use the 
single sales factor method use Schedule A-01, Wisconsin Single Sales Factor Apportionment Data for Nonspecial-
ized Industries, to compute their apportionment percentage. 
However, certain specialized industries do not use the single sales factor method. Instead, they apportion their in-
comes under provisions of the Wisconsin Administrative Code, or in the case of insurance companies, under a sep-
arate subchapter of the Wisconsin Statutes. Companies that don’t use the single sales factor include: 
• Direct air carriers  
• Interstate air freight forwarders affiliated with a direct air carrier 
• Motor carriers  
• Railroads  
• Pipeline companies  
• Financial organizations, including financial institutions, brokers-dealers, investment advisers, investment compa-
  nies, and underwriters  
• Telecommunications companies  
• Insurance companies  
Among these specialized industries, financial organizations and insurance companies have single-factor formulas 
that are similar to the single sales factor. Financial organizations use a receipts factor, and insurance companies use 
a premiums factor.  
The apportionment schedules consist of the following: 
• Schedule A-02, Wisconsin Apportionment Percentage for Interstate Financial Institutions,  
• Schedule A-03, Wisconsin Apportionment Percentage for Interstate Motor Carriers,  
• Schedule A-04, Wisconsin Apportionment Percentage for Interstate Telecommunications Companies,  
• Schedule A-05, Wisconsin Premiums Factor for Insurance Companies,  
• Schedule A-06, Wisconsin Receipts Factor for Interstate Brokers-Dealers, Investment Advisors, Investment Com-
  panies, and Underwriters,  
• Schedule A-07, Wisconsin Apportionment Percentage for Interstate Air Carriers,  
• Schedule A-08, Wisconsin Apportionment Percentage for Broadcasters,  
• Schedule A-09, Wisconsin Apportionment Percentage for Interstate Railroads,  
• Schedule A-10, Wisconsin Apportionment Percentage for Interstate Pipeline Companies, or  

IC-506 (R. 12-24)                                     20

- 21 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• Schedule A-11, Wisconsin Apportionment Percentage for Interstate Air Freight Forwarders Affiliated with a Direct
Air Carrier.

Nonapportionable Income

A corporation or combined group required to use apportionment may have nonapportionable income. Nonapportion-
able income is income which is allocable directly to a particular state. It includes income or loss derived from the sale
of nonbusiness real or tangible personal property or from rentals and royalties from nonbusiness real or tangible
personal property. This income is assigned to the state where the property is located.
Nonapportionable income also includes income that is realized from the sale of or purchase and subsequent sale or
redemption of lottery prizes if the winning tickets were originally bought in Wisconsin.
Total nonapportionable income (or loss) is removed from net income before the apportionment percentage is applied.
The amount allocable to Wisconsin is then combined with the Wisconsin share of apportionable income to arrive at
Wisconsin net income. If a corporation has nonapportionable income, it must report that income on Form N, Wiscon-
sin Nonapportionable, Separately Accounted, and Separately Apportioned Income.
CAUTION: Intangible income of a personal holding company is apportionable unless it qualifies as nonapportionable
income under the same standard that applies to other corporations.

Separately Apportioned Income

A corporation that is a combined group member may have income that is required to be apportioned separately from
the group’s combined unitary income. This may happen in cases where the member has income or loss from the
unitary business that is excluded from combined unitary income under the water’s edge rules. It may also happen in
cases where the member has apportionable income or loss from a separate unitary business. In either case, the
corporation would complete Form N to report the separately apportioned income. See the Form N instructions for
details.

Corporate Partners or LLC Members

A corporation that is a general or limited partner of a partnership must include its share of the numerator and denom-
inator of the partnership’s apportionment factors in its own apportionment factors. A corporation that is a member of
a limited liability company (LLC) treated as a partnership for federal tax purposes must include its share of the nu-
merator and denominator of the LLC’s apportionment factors in its own apportionment factors.
Note: A corporation that is a general or limited partner in a partnership or a member of an LLC treated as a partnership
should obtain a detailed breakdown of the partnership’s or LLC’s apportionment factors so the corporation can include
its share of those factors in the computation of its own apportionment factors
However, income from a partnership or LLC may be nontaxable under the principles of the U.S. Supreme Court
decision in Allied-Signal v. Director, Div. of Taxation, 504 U.S. 768 (1992), if the investment is passive and does not
serve an operational function. In this case, the corporation would not include its share of the partnership’s or LLC’s
apportionment factors in the numerator and denominator of its apportionment factors. Remove this item of income by
completing Form C.

Separate Accounting

A corporation that has income or loss from a business outside Wisconsin that is not part of a unitary business cannot
use apportionment. Instead, it must determine the income attributable to Wisconsin by separate accounting. Under
separate accounting, the corporation must keep separate records of the sales, cost of sales, and expenses for the
Wisconsin business. The corporation uses Form C, Wisconsin Allocation and Separate Accounting Data, to compute
the amount attributable to Wisconsin by separate accounting and uses Form N, Wisconsin Nonapportionable, Sepa-
rately Accounted, and Separately Apportioned Income, to report the separate accounting amount. This is because
the income determined under separate accounting from Form C, line 16 is entered on Form N, line 6.
A unitary business may use separate accounting only with departmental approval. In the application for approval, the
corporation must explain, in detail, why separate accounting more clearly reflects the corporation’s Wisconsin income.
See the instructions for Form C for how to obtain approval to use separate accounting.

IC-506 (R. 12-24) 21

- 22 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Treatment of Specialized Industries and Entities

Foreign Sales Corporations (FSCs)
FSCs no longer receive special treatment for Wisconsin. The income and tax of FSCs are computed in the same
manner as for other corporations.
Interest Charge Domestic International Sales Corporations (IC-DISCs)
IC-DISCs have no special status for Wisconsin tax purposes. An IC-DISC that is a viable corporation with substance
and has nexus in Wisconsin is taxed like any other corporation. However, if an IC-DISC doesn’t carry on any sub-
stantial business activities and does nothing to earn the income that it reports, its net income is allocated to the
corporation that earned the income.
Insurance Companies
An Insurance company may be required to make certain adjustments that are unique to insurance companies. These
adjustments include:
• Adding back loss carryforward deducted in the calculation of federal taxable income and dividend income ex-
cluded from federal taxable income,
• Subtracting nontaxable income attributable to life insurance operations,
• Reducing current year net business loss by the amount of dividends received deduction,
• Adjusting net tax liability so that it doesn’t exceed 2% of gross premiums plus 7.9% of income realized from lottery
prizes.
These adjustments are computed on Wisconsin Form 6I, Wisconsin Adjustments for Insurance Companies. Form 6I
is prepared for each combined group member that is an insurance company. The amounts on Form 6I flow through
to Form 6, Part II, line 2i, Form 6, Part II, line 4o, or Form 6, Part III, line 6. See the Form 6I instructions for details.
If an insurance company is a small company as defined in section 831(b)(2), IRC, the company may elect to be taxed
on taxable investment income as provided in section 831(b), IRC, rather than on net income.
Personal Holding Companies
Personal holding companies no longer receive special treatment for Wisconsin. The intangible income of a personal
holding company is apportionable income unless it qualifies as nonapportionable income.
RICs, REMICs, REITs, and FASITs
Corporations that qualify as regulated investment companies (RICs), real estate mortgage investment conduits
(REMICs), real estate investment trusts (REITs), or financial asset securitization investment trusts (FASITs) under
the IRC cannot be included in a combined group. Rather, they must file as separate entities on Form 4. See sec. Tax
2.61(2)(c), Wisconsin Administrative Code, for details.
Tax Exempt Organizations
A tax-exempt corporation with unrelated business taxable income as defined in section 512, IRC, may be included in
a combined group. If it meets the three tests presented in the section Separate Return or Combined Return, the
corporation is in a combined group, and is included in the combined group’s Form 6. If the corporation is not in a
combined group, it files Form 4T, Wisconsin Tax Exempt Organization Business Franchise or Income Tax Return.
Urban Transit Companies
Certain urban transit companies are subject to a special tax under sec. 71.39, Wis. Stats. Contact the department for
further information.

General Form Instructions

• Complete pages 1 through 14 of Form 6 and all applicable schedules referenced on Form 6.
• Enter the corporation's full name on Form 6, Part VI. For all other Parts, enter the federal employer identification
number and as much of the corporation's name that will fit in the space provided.

IC-506 (R. 12-24) 22

- 23 -

Enlarge image

                               2024 Form 6 Instructions for Combined Returns 
 
• If a foreign company does not have a FEIN because they are not required to obtain one, the foreign company 
  should enter all 9's in the FEIN field. 
• Do not enter “See attached” instead of completing the entry spaces. If more space is needed, submit separate 
  sheets using the same size and format as the printed forms. 
• Round cents to the nearest whole dollar by eliminating amounts less than 50 cents and increasing amounts from 
  50 cents through 99 cents to the next higher dollar.  
• Do not write "None" on the amount lines if there is not an entry for the lines. Instead, leave the lines blank.   

 CAUTION: Federal line numbers referred to on Form 6 are based on the information available when the instruc-
 tions were completed and may change if the IRS makes subsequent modifications. 
                                                                                                                     
Line-by-Line Instructions for Form 6, Page 1 

Header – Before completing items A through D, fill in the combined group’s 2024 taxable year at the top of the form if 
filing a fiscal-year or short period return, and enter the designated agent’s name and address. The name and address 
information should be written on single lines. Do not stack the information on the lines. If more room is needed, 
abbreviate where possible.  
Item A. Federal Employer Identification Number –   Enter the designated agent’s federal employer identification 
number (FEIN).  
Item B. No Business Transacted in Wisconsin –   If the corporation was incorporated under Wisconsin law or li-
censed to do business in Wisconsin but had no property or activity (nexus) in Wisconsin for the taxable year, or is 
protected from filing tax returns because of Public Law 86-272, check here. Submit a complete copy of the corpora-
tion’s federal return with the Form 6. 
Item C. State and Year of Incorporation –   Enter the 2-letter postal abbreviation for the state (or name of the foreign 
country) under whose laws the designated agent corporation is organized and the year of incorporation. 
Item D1. Amended Return –   Check here if this is an amended return and include Schedule AR. Schedule AR is 
used to provide a detailed explanation of the changes made, including any supporting form or schedule. Do not 
include a copy of the original return with the amended return. File the amended return electronically, see Filing Meth-
ods. 
Item D2. First Return - Check here if this is the first year a Wisconsin return is filed because the corporation wasn’t 
in existence or didn’t do business in Wisconsin in prior years.  
Item D3. Final Return – Check here if the corporation ceased to exist or withdrew from Wisconsin during the year 
and will no longer be filing Form 6. If the corporation liquidated, provide a copy of the plan of liquidation and federal 
Form 966. Note: checking this box will not close all accounts with the department; only the corporation account will 
close. 
Item D4 and D5. Short Period – Check the applicable line if a short period return is being filed due to a change in 
the corporation’s accounting period or a stock purchase or sale. 
• Be sure to use the correct year's tax return when filing for a short period. If the tax returns are not yet available, 
  wait until the returns become available and file under extension. For example, if a taxpayer has a short period 
  from January 1, 2025, through March 31, 2025, the 2025 Form 6 will not be ready by July 15, 2025 (unextended 
  due date for a March 31 year-end).  
• Wisconsin law provides for an automatic 7-month extension to file the return, so filing under extension will allow 
  the correct years return to be filed when the 2025 Form 6 is available (typically the middle of September 2025).  
  Note that an extension does not extend the time to pay a balance due. To avoid interest charges, pay the amount 
  due by the unextended due date. 
Item D6. Controlled Group Election  
• Check the box if the group wishes to make the controlled group election and attach a statement which provides 
  all of the following in order for the election to be effective: 
  o  A list of every corporation in the commonly controlled group.  
  o  A statement that each corporation has agreed to be bound by the election.  
  o  A statement that the election shall apply to any member that subsequently enters the group.  
 
IC-506 (R. 12-24)                                       23

- 24 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• What the Controlled Group Election Does
o If a group makes the controlled group election, the entire commonly controlled group is deemed to be en-
gaged in a single unitary business, regardless of whether the companies are actually engaged in a unitary
business. Additionally, all income of the commonly controlled group is considered to be apportionable income
of that unitary business.
o The controlled group election is binding for the taxable year it is elected and for the next nine taxable years.
Note: The controlled group election may simplify combined return filing because it eliminates the need to deter-
mine which corporations are engaged in the unitary business (Test 2). The controlled group election does not
have any effect on the commonly controlled group (Test 1) or on water’s edge (Test 3). The election applies for
a ten-year period.
• Requirements for Controlled Group Election. Any commonly controlled group is eligible to make the controlled
group election, provided it is timely made. To be effective for the taxable year 2024, the election must be made
on a timely filed 2024 Form 6. A return filed under extension is considered timely filed.
• Section Tax 2.63, Wisconsin Administrative Code, provides more information about the continuity of the con-
trolled group election, including rules that apply in cases of corporate reorganizations.
Line 1. Combined Unitary Income – Complete pages 2 through 7 to compute the amount to enter on Form 6, page
1, line 1. The amount on Form 6, page 1, line 1 must equal the amount on Form 6, Part II, line 8. This is the combined
unitary income of the group. However, this amount does not include non-sharable net capital loss carryovers or capital
gain/loss items that are not includable in combined unitary income. See the instructions to Form 6CL for details.
Line 2. Wisconsin Apportionment Percentage – If the combined group is using apportionment, complete a Wis-
consin Schedule A-01, A-02, A-03, A-04, A-05, A-06, A-07, A-08, A-09, A-10, or A-11, as applicable, separately for
each member of the group.
• Then, enter the numerators and denominators from Schedule A-01 to - A-11, as applicable, on Form 6, Part III,
lines 1a and 1b. The combined group's apportionment percentage will be computed on line 1d. See the instruc-
tions to Schedule A-01 to A-11 (as applicable) for details. Also see the General Instructions for Apportionment
presented earlier in these instructions.
• If the combined group doesn’t use apportionment because it does business only in Wisconsin, check the box and
enter “100.0000%.”

Note: On line 2, Fill all spaces to the right of the decimal point. Round to the nearest ten-thousandths of a
percent (for example, 12.3456%)

Line 4. Wisconsin Nonapportionable and Separately Apportioned Income – Complete this line only if an amount
is entered on Form 6, Part II, line 6 and some of the income excluded from combined unitary income is allocable or
apportionable to Wisconsin. For each applicable member, compute this amount on Form N, line 14, and enter it on
Form 6, Part III, line 4 for each member. On line 4 of page 1, enter the combined total from Form 6, Part III, line 4.
See the instructions to Forms N for details.
Line 6. Net Capital Loss Adjustment – Enter the combined total from Form 6, Part III, line 5. For each applicable
member, this amount represents an additional deduction allowable to the member to account for net capital loss
carryovers that could not be shared with the rest of the group. To compute the amount on line 5 of Part III, prepare
Form 6CL, Wisconsin Capital Loss Adjustment, for each applicable member. See the instructions for Forms 6CL and
Form 6, Part III, line 5 for details.
Line 8. Loss Adjustment for Insurance Companies – Enter the combined total from Form 6, Part III, line 6. This is
where insurance companies adjust their current year net business loss so that the carryforward to next year is com-
puted without regard to the dividends received deduction, as required under sec. 71.45(4), Wis. Stats. For each
applicable insurance company in the group, compute this amount on line 24 of Form 6I. See the Form 6I instructions
for details.
Line 10. Wisconsin Net Business Loss Carryforward – Enter the combined total from Form 6, Part III, line 7. In
Part IV of Form 6, each combined group member applies its own net business loss carryforward against its own
income and accounts for any net business loss carryforwards that are eligible to be shared. See the Part IV instruc-
tions for details.
See section Tax 2.61(9), Wisconsin Administrative Code, for rules that explain when net business loss carryforwards
may be shared among combined group members and how the sharing is administered.

IC-506 (R. 12-24) 24

- 25 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

CAUTION: On line 10, do not enter the sum of all members’ amounts from Form 6BL. First compute Form 6, Part
IV for each member to determine the amount of loss eligible to be used. On line 10, enter the combined total of all
the members’ amounts on Form 6, Part III, line 7

Line 11. Wisconsin Net Income (Loss) – Subtract line 10 from line 9. If line 9 shows a loss, enter the loss from line
9 on line 11.
If there is excess income inclusion from a real estate mortgage investment conduit, check the box and see the in-
structions for Part III, line 8.
Line 12. Gross Tax – Enter total from all members Form 6, Part III, line 9 combined total column.
Line 13. Nonrefundable Credits – Enter the amount from the combined total column of Form 6, Part III, line 10. On
Form 6, Part V, each combined group member applies its own available credits against its own tax liability, and also
applies any research credits that are eligible to be shared with the other members of the group. See the Part V
instructions for details.
If any member of the group is sharing its research credits, complete Form 6CS, Sharing of Research Credits. See
the Form 6CS instructions for details of what research credits may be shared and how to compute the shared amount.
Also see sec. Tax 2.61(10), Wisconsin Administrative Code, for rules that apply to sharing research credits.
CAUTION:
1. On line 13, do not enter the sum of all members’ available credits. First compute Form 6, Part V for each member
to determine the credit amount eligible to be used. On line 13, enter the sum of the combined total of all members'
credits from Form 6, Part III, line 10.
2. Two Wisconsin nonrefundable credits may be transferred or sold to other Wisconsin taxpayers, the Supplement
Historic Rehabilitation, and the Angel Investment Credit. Credit amounts transferred during the tax year are not
included on Line 13.
Line 14. Net Tax – Subtract line 13 from line 12. If line 13 is more than line 12, enter zero (0).
Line 15. Economic Development Surcharge – Enter the sum of each member’s economic development surcharge
from the combined total column of Part III, line 11c of Form 6. See the Part III, line 11 instructions for details.
Line 16. Endangered Resources Donation –A donation supports the preservation and management of more than
200 endangered and threatened Wisconsin plants and animals. It also helps protect Wisconsin’s finest remaining
examples of prairies, forests, and wetlands.
• Support endangered resources in Wisconsin. The donation amount on line 16 will reduce a refund or be added
to tax due.
• Donations can be made online at the following web site:
• https://www.billerpayments.com/app/donationsui/?bsn=swidnrdonations#/donations/payment A check also
be sent directly to the: Endangered Resources Fund, Department of Natural Resources
PO Box 7921, Madison, WI 53707-7921.
Line 17. Veterans Trust Fund Donation –Use this line to make a donation to the Wisconsin Department of Veterans
Affairs for the benefit of veterans or their dependents. The donation will either reduce a refund or increase a tax due.
Line 19. Estimated Tax Payments – In general, the designated agent must make estimated payments on behalf of
the entire combined group. Enter the total estimated tax payments applicable to the period included in the combined
return, regardless of whether those payments were made by designated agent or by other members of the combined
group. Include EFT payments, payments made with a Form Corp-ES voucher, or overpayments applied from prior
years’ returns, minus any “quick refund” applied for on Form 4466W.
Line 20. Wisconsin Tax Withheld – Enter the sum of each member’s Wisconsin tax withheld as reported on the
combined total column from Form 6, Part III, line 12. See the Part III, line 12 instructions for details. If this is an
amended return, enter the Wisconsin tax withheld reported on the original return, unless the amount originally re-
ported was incorrect.
Line 21. Refundable Credits – Enter the sum of each member’s refundable credits from the combined total column
of Form 6, Part III, line 13. See the Part III, line 13 instructions for details.
Line 22. Amended Return - Amount Previously Paid - Complete this line only if this is an amended 2024 Form 6.
Fill in the amount of tax paid with the original Form 6 plus any additional amounts paid after it was filed.

IC-506 (R. 12-24) 25

- 26 -

Enlarge image

                                     2024 Form 6 Instructions for Combined Returns 
 
Fill in only the portion actually paid. Also, include any additional tax that may have resulted if the original return was 
changed or audited. This includes additional tax paid with a previously filed 2024 amended return and additional tax 
paid as a result of a department adjustment to the return. Do not include payments of interest or penalties. 
Line 24. Amended Return - Amount Previously Refunded -  Complete this line only if this is an amended 2024 
Form 6. Fill in the refund from the original 2024 return (not including the amount applied to the 2025 estimated tax).  
If the refund was reduced because of underpayment interest or penalties, fill in the amount of the refund before the 
reduction for underpayment interest or penalty. If the 2024 return was adjusted by the department, fill in the refund 
shown on the adjustment notice.. If the adjustment notice shows a tax due rather than a refund, complete line 22 
instead of line 24. 
Line 26. Interest, Penalty, and Late Fee Due –   The combined group is generally treated as a single corporation for 
purposes of determining required estimated payments and any interest, penalty, or late fee due. See the instructions 
to Form U for details. Enter the amount from Form U, line 17 or 26. Check the box if underpayment interest is figured 
using the annualized income installment method on Form U, page 2. 
• If an amended return is filed and interest for underpayment of estimated taxes was previously assessed, complete 
  an amended Form U, Part I, in accordance with the instructions. Enter the difference between the underpayment 
  interest from the amended Form U, line 17, and the amount previously paid on Form 6, line 26. Show an over-
  payment as a negative number. File Form U with the amended return.  
• Otherwise, leave line 26 blank. The department will compute interest on the amount of refund approved or tax 
  owed. 
Line 27. Amount Due –   If the total of lines 18 and 26 is larger than line 25, subtract line 25 from the total of lines 18 
and 26. Pay by electronic funds transfer through My Tax Account, the department's free online business tax system, 
or mail  a  check with  a  2024  Form Corp-ES, Corporation Estimated  Tax Voucher,  to the  address shown on the 
voucher. Otherwise, if the electronic filing waiver is approved, paper clip the check to the front of Form 6.  
Line 28. Overpayment – If line 25 is larger than the total of lines 18 and 26, subtract the total of lines 18 and 26 from 
line 25. 
CAUTION: If a development zones investment credit must be recaptured because the property is disposed of or 
ceases to be qualified property before the end of the recapture period, add the amount from line 11 of the schedule 
located on page 5 of the Schedule DC instructions to the tax due on line 27 or reduce the overpayment on line 28. 
Line 29. 2025 Estimated Tax – Enter the amount of any overpayment from line 28 that is to be credited to the 
combined group’s 2025 estimated tax. The balance of any overpayment will be refunded. An overpayment shown on 
a final return will be refunded to the designated agent. These payments cannot be claimed on the surviving corpora-
tion’s return in a merger situation. 
Changing an Election to Apply a Refund to Estimated Tax 
Section 71.29(3), Wis. Stats., provides an election to apply all or a portion of a claimed refund to the following year's 
estimated tax payments, provided the refund has not been paid or applied elsewhere (for example, against a delin-
quent tax liability).  
An election to apply a refund to estimated tax may be changed to: 
• request payment of the refund, 
• credit the refund against an amended return tax liability for any year, or 
• credit the refund against a notice of amount due for any year. 
Notification of a change in election must occur on or before the unextended due date of the following year's tax return 
or before the following year's tax return is filed, whichever is earlier. 
The change in election must be in writing and attached to an amended return or sent via email, fax, or letter to: 
• DORFranchise@revenue.wi.gov 
•  Fax: (608) 267-0834 
•  Wisconsin Department of Revenue 
  Mail Stop 5-144 
  PO Box 8906, Madison WI 53708-8906 
 
IC-506 (R. 12-24)                                 26

- 27 -

Enlarge image

                                     2024 Form 6 Instructions for Combined Returns 
 
If a timely election to move the estimated payments is not made, any tax due on the return is subject to interest from 
the unextended due date of the return until the date paid. Interest is due regardless of whether the original amount 
of estimated payments exceeded the tax due on the return because the estimated payments were moved to the next 
taxable year.  
Amended Returns 
If this is an amended return and the 2025 return has already been filed, include on line 29 the overpayment claimed 
as a credit on the 2025 return or on the previously filed original or amended 2024 return. Otherwise, allocate the 
overpayment from line 28 between line 29 and line 30.   

Form 6, Page 2         

Line 1. Net Income from Federal Consolidated Return - Differing Taxable Years. In general, the combined return 
will use the same taxable year as the federal consolidated return. However, if there is more than one federal consol-
idated return and the consolidated returns use different taxable years, the information entered on line 1 should be for 
the taxable year that is included in this combined return. Generally, this is the taxable year that ended during the 
combined group’s taxable year. 
•  If a federal consolidated group uses a different taxable year than the combined group and those members’ in-
   come is included in this return, prepare a separate income statement for the months included in the combined 
   group’s taxable year, then prepare separate income statements for all members of that federal consolidated 
   group and include the total from those separate income statements on line 1. 
•  More Than Three Federal Consolidated Groups. If there are more than three federal consolidated groups in 
   the combined group, enter the information for the two largest federal consolidated groups on line 1, respectively. 
   Then prepare a separate schedule to identify the remaining federal consolidated groups and their amounts from 
   Form 1120, line 28. On line 1, enter the sum of the Form 1120, line 28 amounts from the separate schedule and 
   enter “See attached” on the line for Parent Company Name. 
Line 2. Corporations in Combined Group Which Are Not in Federal Consolidated Return – Examples of corpo-
rations included in the combined group which are not in the federal consolidated return include: 
•  Corporations with Less Than 80% Common Ownership –             Identify any companies that are in the combined 
   group but are not included in a federal consolidated return because they do not meet the 80% ownership test 
   required to file a federal consolidated return. On a separate schedule, list each of the companies identified, its 
   federal employer identification number (FEIN), and federal taxable income from Form 1120, line 28 or from which-
   ever federal form applies to the corporation. 
•  Foreign Corporations – Identify any companies that are in the combined group but are not included in a federal 
   consolidated return because they are foreign corporations. On a separate schedule, list each of those companies, 
   its federal employer identification number (FEIN), and federal taxable income. 
•  Include all income that is effectively connected with the conduct of a trade or business in the United States, plus 
   any other U.S. source income. For federal purposes, these amounts may have been reported on Form 1120-F 
   or they may have been amounts for which federal income tax was withheld by the payer. 
   Note: If federal income was reduced by provisions of a federal treaty, enter the amount after applying the provi-
   sions of the federal treaty. If a federal treaty reduced the federal tax rate, include the entire amount of federal 
   income, including the income to which the reduced rate applied. 
Other Corporations Not in Consolidated Group – Identify any other companies that are in the combined group but 
are not included in a federal consolidated return. On a separate schedule, list each of those companies, its federal 
employer identification number (FEIN), and federal taxable income, and explain why the company is not includable 
in a federal consolidated return.  
Line 4. Corporations in Federal Consolidated Return Which are Not Combined Group Members –  Identify all 
companies included in the federal consolidated return(s) on line 1 that aren’t includable in the combined group. 
For each company  identified, determine its “separate taxable income” as computed for federal income tax purposes 
under Treas. Reg. §1.1502-12. That is, determine its federal taxable income without regard to any items that had to 
be accounted for at the consolidated group level, such as capital gains and losses, section 1231 gains and losses, 
involuntary conversions, and charitable contributions.  
Corporations Not Engaged in the Combined Group’s Unitary Business – On a separate schedule, list each of 
those companies, its federal employer identification number (FEIN), and federal separate taxable income. Enter the 

IC-506 (R. 12-24)                                       27

- 28 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

total of the federal separate taxable incomes on line 4.
CAUTION: If the group made the controlled group election, do not enter any amounts on line 4. Under the controlled
group election, all corporations in the commonly controlled group are considered to be engaged in the same unitary
business.
Corporations Not in the Combined Group Under Water’s Edge Rules – Identify any companies included in the
federal consolidated return(s) that are completely excluded from the combined group under the water’s edge rules,
but do not include companies already accounted for on line 1. On a separate schedule, list each company excluded
under the water’s edge rules, its federal employer identification number (FEIN), and federal separate taxable income.
Enter the total of the federal separate taxable incomes on line 4.
The following is an explanation of the water’s edge rules:
• Water’s Edge Rules in General. The water’s edge rules are explained in sec. Tax 2.61(4), Wisconsin Adminis-
trative Code. In part, these rules provide that if a foreign (non-U.S.) or domestic (U.S.) corporation is an “80/20
corporation,” it may be excluded from a combined group even if it is otherwise part of the group’s unitary business.
• The water’s edge rules also provide that for some corporations, only part of their income from the unitary business
is includable in the combined unitary income, with the remainder accounted for on a separate entity basis. The
instructions for Form N, Wisconsin Nonapportionable, Separately Accounted, and Separately Apportioned In-
come, describe these aspects of the water’s edge rules in more detail.
Note: If a combined group member has some income that is includable in combined unitary income and some that
is excluded under the water’s edge rules, do not report the excluded amount on line 4. Instead, report the excluded
amount on Form N, line 7.
Qualifying as an “80/20 Corporation.” A corporation is considered to be an “80/20 corporation” if 80 percent or
more of its worldwide gross income during the taxable year that would otherwise be includable in the combined return
is “active foreign business income,” as determined in subchapter N of the IRC including income of a subsidiary cor-
poration, and attributable to the active conduct of a trade or business in a foreign country or in a U.S. possession. A
corporation is considered a subsidiary if the parent corporation owns, directly or indirectly, stock with at least 50
percent of the total voting power of the corporation and the stock has a value equal to at least 50 percent of the total
value of the stock of the corporation. An 80/20 corporation may be either a foreign corporation or a domestic corpo-
ration, as long as it meets the active foreign business income test.
“Active foreign business income” means gross income which is both:
• Derived from sources outside the United States, as determined under subchapter N of the IRC and
• Attributable to the corporation’s active conduct of a trade or business in a foreign country or possession of the
United States.
For special rules regarding the 80/20 test as it relates to parent-subsidiary chains, disregarded entities, and part-year
group members, see sec. Tax 2.61(4)(b), Wisconsin Administrative Code.
• Foreign 80/20 Corporations. If an 80/20 corporation is a foreign corporation, then it is not a member of the
combined group unless it elected to be included in a consolidated return for federal purposes.
o If a foreign 80/20 corporation was not included in a federal consolidated return, it is not accounted for on line
4, those corporations are accounted for on line 2.
o If a foreign 80/20 corporation elected to be included in a consolidated return for federal purposes, it is treated
in the same way as a domestic 80/20 corporation, described next.
• Domestic 80/20 Corporations. If a domestic corporation is an 80/20 corporation, then its income includable in
the combined unitary income is limited to only U.S. source income as provided in sections 861 through 865 of
the IRC Further, that U.S. source income must be of one of the following types to be included in combined unitary
income:
o Interest income or income generated from intangible property, regardless of who the payer is.
o Income derived from interest or intangible expenses of other combined group members, to the extent not
already included in 1 above.
o Dividends from a real estate investment trust (REIT) that is not a “qualified REIT” under sec. 71.22(9ad), Wis.
Stats.
o Gains or losses derived from the sale or lease of real or personal property located in the United States.

IC-506 (R. 12-24) 28

- 29 -

Enlarge image

                              2024 Form 6 Instructions for Combined Returns 
 
The expenses attributable to these types of income, including an allocated share of indirect expenses, are also in-
cludable in combined unitary income.  
The water’s edge rules for domestic 80/20 corporations, summarized  above,  are specifically provided in sec. 
71.255(2)(d), Wis. Stats., and sec. Tax 2.61(4)(d)2., Wisconsin Administrative Code. In the statute, the term “consol-
idated foreign operating corporation” is used to describe a domestic 80/20 corporation. The terms “domestic 80/20 
corporation” and “consolidated foreign operating corporation” have the same meaning.  
If a domestic 80/20 corporation (or a foreign 80/20 corporation that elects to be included in a federal consolidated 
return) does not have U.S. source income of the types described in 1. through 4. above, it is not a combined group 
member. Include its federal separate taxable income on line 4. 
Other Corporations Not in the Combined Group –      Identify companies not accounted for on line 4 that are in a 
related federal consolidated group but not the combined group. On a separate schedule, list the name, federal em-
ployer identification number (FEIN) and separate federal taxable income. Additionally, explain why the company is 
not included in the combined group. Enter the total federal separate taxable income of these companies on line 4. 
Line 7. Federal Net Income of Corporations in Controlled Group that are Not in Federal Consolidated Return 
or Combined Return – Enter the total net income, as reported for federal income tax purposes, of all companies 
that are in the controlled group but are not in the federal consolidated return or combined return. Attach a schedule 
identifying each corporation. 
Line 8. Gross Sales – Enter the total gross sales corresponding to the income amount on line 7. Don’t include sales 
that were not includable in federal gross income. 
Lines 9 through 11. Contact Information and Miscellaneous – Provide the information as instructed on the form. 
• Third Party Designee – If a tax preparer or tax preparation firm, or any other person has permission to discuss 
  the 2024 tax return with the Department of Revenue, check “Yes” in the “Third Party Designee” area of the return. 
  Also, fill in the designee’s name, phone number, and any five digits the designee chooses as their personal 
  identification number (PIN). When “Yes,” is checked the department is authorized to discuss with the designee 
  any questions that may arise during the processing of the return. The designee is also authorized to:  
  o  Give the department any information missing from the return,  
  o  Call the department for information about the processing of the return or the status of any refund or pay-
   ment(s), and  
  o  Respond to certain department notices about math errors, offsets, and return preparation.  
  o  The designee is not authorized to receive any refund check, bind the taxpayer to anything (including any 
   additional tax liability), or otherwise represent the taxpayer before the department. To expand the designee’s 
   authorization, Form A-222 (Power of Attorney) must be filed. The authorization will automatically end no later 
   than the due date (without regard to extensions) for filing the 2025 tax return. 
• Signatures – An officer of the designated agent corporation must sign at the bottom of page 2. If the return is 
  prepared by someone other than an employee of the corporation, the individual who prepared the return must 
  sign the form in the space provided for the preparer’s signature and furnish the preparing firm’s federal employer 
  identification number. A self-employed individual must enter “PTIN” and the preparer tax identification number in 
  the space for the preparer’s federal employer identification number. 

Part I: Modified Federal Taxable Income 

Enter the corporation's federal employer identification number and as much of the corporation's name that will fit in 
the space provided.  
Enter the information for each member in a separate column. If there are more than three members, use more pages 
3 and 4. Enter the elimination adjustments for all members in elimination adjustments column as positive and neg-
ative values. A positive value will increase the total of the member's amounts reported in the combined total column 
and a negative value will decrease the total of the member' amounts reported in the combined total column.  If more 
than three members exist, enter the elimination entries on the final pages 3 and 4 completed. Once all members have 
been entered and the elimination adjustments column completed, compute the combined total column for all the 
members of the group by summing the amounts in the member's columns with the elimination adjustments.  
For example, if there are seven members in the combined group, enter members one through three on pages 3 and 
4 of Form 6, leaving the elimination adjustment column and combined total column blank. Next, enter members four 
through six on pages 3 and 4 of Form 6, leaving the elimination adjustments column and combined total columns 

IC-506 (R. 12-24)                                   29

- 30 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

blank. Finally, complete another page 3 and 4 of Form 6 for the seventh and final member. Leave the other two
columns blank, enter the elimination adjustments as positive and negative values, and enter the combined totals for
all members of the group in the final column.
Note: A member should only appear in one column of Form 6. If the member has two taxable periods due to filing
two short period returns, the information should be combined into one column and an attachment included with the
return detailing the computation of the amounts included in the column.
For example, Member B files two short period returns – the first for the taxable period of January 1, 2024 through
March 31, 2024 and the second for the taxable period of April 1, 2024 through December 31, 2024. Member B should
only be included in one column of Form 6. The items of income, deduction, and credit for both periods should be
combined into one column. For the taxable period on Form 6, Part VI, line 2, enter a beginning period of January 1,
2024, and an ending period of December 31, 2024.
Lines 1 through 26. Modified Federal Taxable Income – Enter the information for each member of the combined
group from the member's federal corporate return. Lines 1 through 26 are identical to federal Form 1120. If a form
other than federal Form 1120 is being used, enter the information on lines 1 through 26 that corresponds to the form
being filed. Be sure the taxable income reported on line 28 is the taxable income for the form being filed.
Lines 29 through 33 – If the elimination adjustments on lines 1 through 26 already accounted for the recomputed
capital gains, charitable contributions, and intercompany transactions, skip lines 29 through 33 and leave the lines
blank.
Line 29. Net Capital Gains Included on Line 28 – Enter the total of the net capital gains reported on the consolidated
return(s) shown on Form 6, page 2, line 1, and on the separate federal returns for any companies included on Form
6, page 2, line 2. Generally, these amounts are on line 8 of Form 1120 or 1120-F. Enter as a negative number in the
columns for each member. The elimination adjustment column may be positive or negative.
Line 30.Recomputed Net Capital Gain -- Line 30 is generally computed by applying the capital loss limitation to
the group as a whole in the same manner it would apply to a federal consolidated group under Treas. Regs. §1.1502-
22 and 1.1502-23. If there are no capital losses to offset the capital gains, do not allocate the capital gains among
the members of the combined group. The capital gain income is reported by the member(s) that generated it.
To compute the amount on line 30, complete a separate federal Schedule D, Capital Gains and Losses, and the
federal schedules referenced in Schedule D, including federal Form 4797, Sales of Business Property, and federal
Form 4684, Casualties and Thefts, where applicable, as if the Wisconsin combined group is a federal consolidated
group, but with two important exceptions:
• Do not include any net capital loss carryovers that are non-sharable losses.
• Do not include any gain or loss amounts that aren’t includable in combined unitary income.
Each of these exceptions is described in detail below. If the computation on the federal Schedule D for the combined
group results in a net capital gain, enter that net capital gain as a positive amount on line 30. Submit a copy of the
recomputed federal Schedule D, federal Form 4797, and federal Form 4684, as applicable, with the return.
Non-sharable Losses. Non-sharable capital losses that cannot be included in the computation of line 30 are those
that originated:
• In a taxable year beginning before January 1, 2009, or
• In the combined unitary income of another combined group, or
• In transactions that were reportable on a separate entity basis.
The rules which characterize a net capital loss as sharable or non-sharable are the same as those that characterize
a net business loss as sharable or non-sharable. For special rules that apply in cases of subgroups and a corpora-
tion’s options regarding sharable losses, see sec. Tax 2.61(9), Wisconsin Administrative Code.
CAUTION: Do not include net capital loss carryovers from taxable years beginning before 2009 in the computation
of the group’s net capital gain on line 30.
Combined group members that have non-sharable capital loss carryovers may still use those carryovers to offset
their share of the combined group’s net capital gain. Those members should use Wisconsin Form 6CL, Capital Loss
Adjustment, to claim their non-sharable capital loss carryovers. See the Form 6CL instructions for details.
Alternatively, a combined group member may choose to carry back a non-sharable capital loss carryover to a taxable
year beginning before 2009 to the extent allowed under section 1212 of the IRC.
Gain or Loss Amounts Not Includable in Combined Unitary Income. A combined group member’s capital gains

IC-506 (R. 12-24) 30

- 31 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

and losses, section 1231 gains and losses, or gains and losses from involuntary conversions may not be includable
in combined unitary income because they are attributable to a separate unitary business or because they are ex-
cluded under the water’s edge rules.
In either case, instead of including these items in the computation of the group’s net capital gain on line 30, report
them separately for that member when completing Part II of that member’s Form N, Wisconsin Nonapportionable,
Separately Accounted, and Separately Apportioned Income. See the Form N instructions for details.

Note: If a combined group member’s capital gains and losses, section 1231 gains and losses, or gains and losses
from involuntary conversions are not includable in combined unitary income, report them on Part II of Form N, not on
line 30.

Line 31. Sum of Charitable Contributions, Net Section 1231 Losses, Involuntary Conversions – Enter the sum
of the charitable contributions deduction, net section 1231 losses, and losses from involuntary conversions reported
on the consolidated return(s) shown on Form 6, page 2, line 1 and on the separate federal returns for any companies
included on Form 6, page 2, line 2. Charitable contributions are generally on line 19 of federal Form 1120 or 1120-F.
Section 1231 losses and losses from involuntary conversions are generally accounted for on federal Form 4797.
Enter as a positive number in the columns for each member. The elimination adjustment column may be positive or
negative.
Line 32. Sum of Recomputed Charitable Contributions, Net Section 1231 Losses, Losses from Involuntary
Conversions – Enter the sum of the charitable contribution deduction and the deduction for net section 1231 losses
and involuntary conversions, as applicable, applying limitations at the combined group level. Enter as a negative
number in the columns for each member. The elimination adjustment column may be positive or negative. Further
details are shown below:
• Charitable Contributions. Determine the charitable contribution deduction under Treas. Reg. §1.1502-24 as if
the combined group is a federal consolidated group. Unlike net capital loss carryovers, unused charitable contri-
bution deduction carryovers may be applied at the group level even if they were incurred in a taxable year begin-
ning before 2009, as long as the carryover period has not expired.
• Net Section 1231 Losses and Losses from Involuntary Conversions. If the computations on the federal
Forms 4797 and 4684 prepared as described in the instructions for line 30 results in a net section 1231 loss, a
loss from involuntary conversions, or both, include those losses on line 32.
Line 33. Adjustment for Intercompany Deferrals – On line 33 apply the provisions of Treas. Reg. §1.1502-13 so
that intercompany transactions between members of the combined group are treated the same way as between
members of a consolidated group for federal purposes.
Compute the amount on line 33 as follows:
• For companies included in both the combined group and a federal consolidated group, reverse out the effect of
adjustments already computed under Treas. Reg. §1.1502-13 for purposes of the federal return.
• For all companies in the combined group, compute adjustments under Treas. Reg. §1.1502-13 as if the combined
group is a federal consolidated group.
• Compute the sum of the amounts derived from 1 and the ordinary income/loss items from 2. and enter the result
on line 33.
The following are specific instructions for computing the amounts in these steps:
Step 1: Reverse Intercompany Adjustments for Federal Consolidated Group. If intercompany adjustments are
recomputed under Treas. Reg. §1.1502-13 for purposes of the federal consolidated return and those adjustments
are included in the amount on Form 6, page 2, line 5, then include on line 33 an amount to offset those adjustments.
This amount may be either positive or negative.
CAUTION: Do not double-count these items on Form 6, Part I, lines 29 and 31, and Form 6, page 2, line 4 when
computing line 33.
Step 2: Compute Intercompany Adjustments for Combined Group. Identify any transactions that took place be-
tween members of the combined group and compute adjustments to defer income, gain, or loss between those
members in the same manner as prescribed for members of consolidated groups under Treas. Reg. § 1.1502-13.
In general, Treas. Reg. §1.1502-13 provides that income, deduction, gain, or loss on transactions between members
of a consolidated group is deferred so that these transactions do not affect the combined group’s income as a whole.
As an example, assume Corporations S and B are in a federal consolidated group. In Year 1, S sells land with a basis

IC-506 (R. 12-24) 31

- 32 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

of $50,000 to B for $80,000. Under Treas. Reg. §1.1502-13, in Year 1, make an adjustment to exclude S’s $30,000
gain from the group’s income.
However, any deferred gain must recognize when a triggering event occurs. For Wisconsin purposes, all the following
are triggering events:
• The buyer resells the object of the deferred intercompany transaction to an entity that is not a member of the
combined group,
• The object of a deferred intercompany transaction is used outside the combined group’s unitary business as a
result of the buyer’s resale, conversion, or transfer of the asset, or
• The buyer and seller are no longer members of the same combined group.
Continuing the previous example, assume in Year 3, B sells the land to P, an unrelated party, for $90,000. In Year 3,
make an adjustment to recognize S’s $30,000 deferred gain from Year 1 in addition to the $10,000 of gain that B
recognized on the sale to P.
However, since Wisconsin did not recognize Treas. Reg. §1.1502-13 for taxable years beginning before January 1,
2009, do not make adjustments to recognize gains or losses deferred under Treas. Reg. §1.1502-13 that were
incurred in taxable years beginning before January 1, 2009.
See Treas. Reg. § 1.1502-13 for more details and examples of how to compute adjustments for various types of
intercompany transactions.
Step 3: Completing Line 33. For the intercompany adjustments computed in Step 2, separate the amounts into
ordinary income/loss items and capital gain/loss items (including section 1231 gains and losses and gains and losses
from involuntary conversions.
Combine the amount computed in Step 1 with the ordinary income/loss items computed in Step 2. If the net effect is
a reduction in the combined group’s income, enter the amount on line 33 as a negative number. If the net effect is an
increase in the combined group’s income, enter the amount on line 33 as a positive number.
Line 34. Other Adjustments Based on Federal Law – Use line 34 to report any other adjustments that are neces-
sary to reconcile the federal taxable income.
CAUTION: On line 34, do not include Wisconsin modifications that should be reported on Form 6, Part II, or sepa-
rately reportable items that should be reported on Form N.
If there are adjustments reported on line 34, on a separate schedule list the name and federal employer identification
number (FEIN) of each company with an amount included on line 34, the amount of adjustment for that company,
and explain why the adjustment is necessary.

Part II: Unitary Income Computation

Enter the corporation's name and federal employer identification number. Enter as much of the corporation's name
that will fit in the space provided. The full corporation's name will be entered on Part VI of Form 6. If a foreign
company does not have a FEIN because they are not required to obtain one, the foreign company should
enter all 9's in the FEIN field.

Additions to Income

Enter the information for each member in a separate column. If there are more than three members, use additional
pages 5, 6, and 7 of Form 6. Enter the elimination adjustments for all members in elimination adjustments column
as positive and negative values. A positive value will increase the total of the member's amounts reported in the
combined total column and a negative value will decrease the total of the member's amounts reported in the combined
total column. If more than three members exist, enter the elimination on the final pages 5, 6, and 7 completed. Once
all members have been entered and the elimination adjustments column completed, compute the combined total
column for all the members of the group by summing the amounts in the member's columns with the elimination
adjustments.
For example, if there are seven members in the combined group, enter members one through three on pages 5, 6
and 7 of Form 6, leaving the elimination adjustment column and combined total column blank. Next, enter members
four through six on pages 5, 6, and 7 of Form 6, leaving the elimination adjustments column and combined total
columns blank. Finally, complete another page 5, 6, and 7 of Form 6 for the seventh and final member. Leave the
other two columns blank, enter the elimination adjustments as positive and negative values, and enter the combined

IC-506 (R. 12-24) 32

- 33 -

Enlarge image

                                   2024 Form 6 Instructions for Combined Returns 
 
totals for all members of the group in the final column. 
Line 2a. Interest Income – Enter interest income received on state and municipal obligations and any other interest 
income that is exempt from federal income tax and isn’t included in federal taxable income. Corporations subject to 
the Wisconsin income tax rather than the franchise tax should not enter interest income on line 2a that is exempt 
from income tax under both Wisconsin and federal law. This includes interest on the following types of obligations:  
• Public housing authority or community development authority bonds issued by municipalities located in Wisconsin  
• Wisconsin Housing Finance Authority bonds  
• Wisconsin municipal redevelopment authority bonds  
• Wisconsin Housing and Economic Development Authority bonds issued on or after December 11, 2003, to fund 
  multifamily affordable housing or elderly housing projects  
• Wisconsin Housing and Economic Development Authority bonds issued before January 29, 1987, except busi-
  ness development revenue bonds, economic development revenue bonds, and CHAP housing revenue bonds 
• Public housing agency bonds issued before January 29, 1987, by agencies located outside Wisconsin where the 
  interest therefrom qualifies for exemption from federal taxation for a reason other than or in addition to section 
  103 of the IRC  
• Local exposition district bonds  
• Wisconsin professional baseball park district bonds  
• Bonds issued by the Government of Puerto Rico, Guam, the Virgin Islands or, for bonds issued after October 16, 
  2004, the Government of American Samoa  
• Local cultural arts district bonds  
• Wisconsin professional football stadium bonds 
• Wisconsin Aerospace Authority bonds 
• Bonds issued on or after October 27, 2007, by the Wisconsin Health and Education Facilities Authority to fund 
  acquisition of information technology hardware or software  
• Conduit revenue bonds issued under sec. 66.0304, Wis. Stats., if the bonds or notes are used to fund multifamily 
  affordable housing projects or elderly housing projects in Wisconsin and the Wisconsin Health and Education 
  Facilities Authority has the authority to issue the bonds. The bonds or notes are used by a health facility to fund 
  the acquisition of information technology hardware or software in Wisconsin and the Wisconsin Health and Edu-
  cational Facilities Authority has the authority to issue the bonds. Bonds or notes issued to fund a redevelopment 
  project or housing project in Wisconsin 
• Bonds issued by the Wisconsin Housing and Economic Development Authority to provide loans to a public affair 
  network  
• Wisconsin Health and Educational Facilities Authority Bonds if the bonds or notes are issued for the benefit of a 
  person who is eligible to receive the proceeds from another entity for the same purpose for which the bonds or 
  notes are issued and the interest income received from the other bonds or notes is exempt from Wisconsin 
  taxation  
• Bonds or notes issued by the Wisconsin Health and Educational Facilities Authority under sec. 231.03(6), Wis. 
  Stats., if the bonds or notes were issued in an amount totaling $35 million or less, and the interest income is not 
  otherwise exempt 
Line 2b. State Taxes – Enter taxes imposed by Wisconsin, any other state, and the District of Columbia that are 
value-added taxes, single business taxes, or taxes on or measured by net income, gross income, gross receipts, or 
capital stock and that were deducted in computing federal taxable income. 
Note: The state taxes added back on line 2 should include all components of the Texas Margins Tax regardless of 
which computation is used. However, the Ohio Commercial Activity Tax is not required to be added back since it is 
deductible. 
Line 2c. Related Entity Expenses –        A corporation must make an addition modification to “add back” expenses 
attributable to transactions with related parties. The expenses that must be added back include the following, if paid, 
accrued, or incurred to a related entity: 
• Interest  
• Rent   
• Management fees  

IC-506 (R. 12-24)                                        33

- 34 -

Enlarge image

                                   2024 Form 6 Instructions for Combined Returns 
 
• Intangible  
However, if the corporation is a combined group member and pays, accrues, or incurs one of these types of expenses 
to another member of the same combined group, do not add those expenses back if the net effect of the transaction 
on combined unitary income was zero. In other words, if the payer’s expense and the corresponding income of the 
member to which the expense was paid are both included in combined unitary income so that they cancel each other 
out.  
Corporations that are partners, LLC members, or beneficiaries of pass-through entities must include on line 2c their 
share of the pass-through entity’s related entity expenses shown on line 22a of Schedule 3K-1 and line 14a of Sched-
ule 2K-1, as applicable. 
Note: If the corporation meets one of the specific conditions provided in the Wisconsin Statutes, the corporation may 
make a subtraction modification on Form 6, Part II, line 4b. 
Definitions Applicable to Line 2c. In determining whether an addback of related entity expenses is necessary, the 
following definitions apply:  
“Related entity” – A related person under one of the following sections of the IRC: 
• Section 267(b), which defines relationships through which taxpayers would be considered “related” for purposes 
  of the disallowance of deduction or loss on transactions between related taxpayers  
• Section 1563, relating to controlled groups of corporations, which is incorporated into section 267 by reference  
• Section 707(b) relating to partnerships which is also incorporated into section 267 by reference. 
A "related entity" also includes certain real estate investment trusts (REITs) if they are not "qualified REITs." For more 
on qualified REITs, see Wisconsin Tax Bulletin #158, page 17, Questions A2 and A3. 
“Interest expenses” –    Interest that would otherwise be deductible under section  163 of the IRC and otherwise 
deductible in the computation of Wisconsin income.  
“Rent expenses”   – Gross amounts that would otherwise be deductible under the IRC, as modified for Wisconsin 
purposes, for the use of, or the right to use, real property and tangible personal property in connection with real 
property, including services rendered in connection with such property, regardless of how reported for financial ac-
counting purposes and regardless of how computed.  
“Management fees” – Expenses and costs, not including interest expenses, pertaining to accounts receivable, ac-
counts payable, employee benefit plans, insurance, legal matters, payroll, data processing, purchasing, taxation, 
financial matters, securities, accounting, or reporting on compliance matters or similar activities, to the extent that the 
amounts would otherwise be deductible in determining net income under the IRC as modified for Wisconsin purposes.  
“Intangible expenses” – Any of the following, to the extent the amounts would otherwise be deductible in determin-
ing net income under the IRC as modified for Wisconsin purposes: 
• Expenses, losses, or costs for, related to, or directly or indirectly in connection with, the acquisition, use, mainte-
  nance, management, ownership, sale, exchange, or any other disposition of intangible property  
• Losses related to, or incurred in connection directly or indirectly with, factoring transactions or discounting trans-
  actions 
• Royalty, patent, technical, and copyright fees  
• Licensing fees  
If a corporation purchases an amortizable intangible asset from a related entity, the amortization expenses on that 
asset are considered intangible expenses and should be added back. 
Schedule RT Filing Requirement for Amount on Line 2c.        If the amount a member reports on line 2c exceeds 
$100,000, the member must file Schedule RT, Wisconsin Related Entity Expenses Disclosure Statement, with its 
return. However, for combined groups using apportionment, multiply the member's amount on line 2c by the appor-
tionment percentage (Form 6, page 1, line 2) for purposes of determining whether the $100,000 threshold for filing 
Schedule RT is met. 
 
Line 2d. Actual distribution of previously taxed income (PTI) aka Previously taxed earnings and  profits 
(PTEP).  PTI/PTEP represents a distribution from a non-US entity that was previously taxed for federal purposes but 
not taxed by Wisconsin. 

IC-506 (R. 12-24)                                   34

- 35 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Line 2e. Expenses Related to Nontaxable Income – Enter expenses included in federal taxable income that are
directly or indirectly related to nontaxable income. Examples of expenses related to nontaxable income include taxes,
interest, and administrative fees related to the production of nontaxable income.
Interest, dividends, and capital gains from the disposition of intangible assets are nontaxable if both of the following
are true:
• The operations of the payer are not unitary with those of the payee, and
• The payer and payee are not related as parent company and subsidiary or affiliates and the investment activity
from which the income is received is not an integral part of a unitary business.
• Income may also be nontaxable under the principles of the U.S. Supreme Court decision in Allied-Signal v. Di-
rector, Div. of Taxation, 504 U.S. 768 (1992), if the investment is passive and does not serve an operational
function.
For corporations subject to the Wisconsin income tax rather than the franchise tax, nontaxable income also includes
interest on United States government obligations.
Also enter on this line any losses included in federal taxable income from disposing of assets if gains from disposing
those assets would have been non-taxable income if the assets were disposed of at a gain.
Line 2f. Basis, Section 179, Depreciation Differences –
Difference in federal and Wisconsin basis of depreciated or amortized assets:
Enter the amount by which the federal deduction for depreciation or amortization exceeds the Wisconsin deduction
for depreciation or amortization. Provide a schedule showing the computation details. These differences can happen
because of IRC sections not adopted for Wisconsin purposes and electing a different depreciation method under the
IRC in effect for Wisconsin purposes. For further information about the differences between federal and Wisconsin
basis and depreciation, see the section titled Conformity with IRC and Exceptions in the Form 6 instructions, as
applicable.
Note: If the total Wisconsin adjusted basis is more than total federal adjusted basis, see the instructions for Form 6,
Part II, line 4j.
Section 179 expenses:
• For taxable years beginning on or after January 1, 2014, sections 179,179A 179B, 179C, 179D, , and 179E of
the IRC related to expensing of depreciable business assets, apply for Wisconsin tax purposes. "Internal Reve-
nue Code" means the federal IRC in effect for the year in which the property is placed in service.
• For further information about the differences between the limitations for federal and Wisconsin purposes, see the
section titled Conformity with IRC and Exceptions in the Form 6 instructions.
Depreciation differences:
• Enter the amount by which the federal deduction for depreciation or amortization exceeds the Wisconsin deduc-
tion. Include a schedule showing the computation details.
• These differences can happen because of IRC sections not adopted for Wisconsin purposes and electing a
different depreciation method under the IRC in effect for Wisconsin purposes.
• For 2014 and beyond, bonus depreciation was reinstituted by the federal government, and an adjustment is
required to account for the depreciation difference because Wisconsin has not adopted federal bonus deprecia-
tion provisions. For Wisconsin purposes, depreciation, depletion, and amortization is computed based on the
IRC in effect on January 1, 2014, and bonus depreciation was not in effect on that date.
Line 2g. Amount by Which the Federal Basis of Assets Disposed of Exceeds the Wisconsin Basis – Enter the
amount by which the federal basis of assets disposed of exceeds the Wisconsin basis. If more than one asset is
disposed of, the bases of the assets may be combined so only one entry on this line. Provide a schedule showing
the computation details.
For example, assume a corporation sold the following assets during the current taxable year:

IC-506 (R. 12-24) 35

- 36 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Federal Basis Wisconsin Basis Difference
Equipment $1,500 $500 $1,000
Machinery 1,000 2,000 (1,000)
Building 20,000 10,000 10,000
Totals $22,500 $12,500 $10,000

The amount to enter on line 2g would be $10,000. If the Wisconsin bases of the assets had exceeded the federal
bases, an entry would be made on Form 6, Part II, line 4k, instead.
The modification may also apply in cases where a parent corporation disposes of subsidiary stock for which the basis
is determined under Treas. Reg. §1.1502-32. See sec. Tax 2.61(6)(f), Wisconsin Administrative Code, for details.
Line 2h. Addition for Credits Computed – Enter the total amount of credits computed on each member's 2024
return from the list provided (except the manufacturing and agriculture credit is the amount computed in 2023).
• Line 2h-a: Business development credit (Schedule BD)
• Line 2h-b: Community rehabilitation program credit (Schedule CM)
• Line 2h-c: Development zones credits (Schedule DC)
• Line 2h-d: Economic development credit (Schedule ED)
• Line 2h-e: Electronics and information technology manufacturing zone credit (Schedule EIT)
• Line 2h-f: Employee college saving account contribution credit (Schedule ES)
• Line 2h-g: Enterprise zone jobs credit (Schedule EC)
• Line 2h-h: Farmland preservation credit (from Schedules FC or FC-A)
• Line 2h-i: Reserved for future use
• Line 2h-j: Reserved for future use
• Line 2h-k: Manufacturing and agriculture credit (credit computed on 2023 Schedule MA-A and/or MA-M)
• Line 2h-l: Research credits (Schedule R)
• Line 2h-m: Reserved for future use
Line 2i. Special Additions for Insurance Companies – If any member of the combined group is an insurance
company, Form 6I must be completed to account for addition modifications that are unique to insurance companies.
Enter the total from Form 6I, line 4.
Line 2j. Other Additions – Enter any other additions to federal income that are not specifically listed in lines 2a-2i
above. Include the numerical code number in the space to the right of the letter.
For example:

CAUTION: Do not enter additions on line 2j that are specifically designated on lines 2a-2i above. For example, if a
depreciation adjustment is passed through from a partnership on Schedule 3K-1, enter the amount on line 2f, not
line 2j.

Other Additions to federal income may include
• 01 Federal capital loss carryovers (if previously deducted for Wisconsin).
• 02 Adjustments required as a result of changes made to the IRC which don’t apply for Wisconsin. For Wisconsin,
the IRC means the federal Internal Revenue Code as amended to December 31, 2022, with exceptions. See
"Conformity with Internal Revenue Code and Exceptions" earlier in the instructions for a list of IRC provisions
adopted and not adopted.
• 03 Adjustments required as a result of making different elections for Wisconsin and federal purposes. For addi-
tional information, see page 8 of Wisconsin Tax Bulletin 214.

IC-506 (R. 12-24) 36

- 37 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• 04 Separately stated items of income and adjustments for differences between the federal and Wisconsin treat-
ment of any items of an S corporation that opts out of Wisconsin tax-option status.
• 05 Other (include a statement detailing the source and amounts).
• 06 For 100% Wisconsin groups: Intercompany transactions (except those to which Treas. Reg. §1.1502-13
already applies) for expenses paid, accrued, or incurred by one member of the combined group to another, are
disregarded so that they neither increase nor decrease a member’s portion of the combined unitary income. This
does not apply to intercompany transactions which occurred in taxable years beginning before January 1, 2009
or to intercompany transactions where the income, expense, gain, or loss would not otherwise be subject to
combination. See Part III, line 2 for more information.
• 07 For 100% Wisconsin groups: Capital gains and losses. The net capital gain or loss, after applying any
sharable net capital loss carryover, is first determined for the combined group as a whole. If the result is a net
capital gain for the group, the net capital gain is assigned to the members that would have a net capital gain from
the unitary business if they were not members of the combined group, in proportion to the amount of that net
capital gain. If the result is a net capital loss for the group, the net capital loss is assigned to the members that
would have a net capital loss from the unitary business if they were not members of the combined group, in
proportion to the amount of that net capital loss. Then each member computes its net capital gain or loss from
separate entity items. See Part III, line 2 for more information.
• 08 For 100% Wisconsin groups: Basis adjustments. A combined group member’s basis in stock of a subsidiary
that is a member of the same combined group is adjusted to reflect the subsidiary's distributions and items of
income, gain, deduction, and loss taken into account while the subsidiary was a member of the combined group.
Intercompany interest and other expenses are included in these adjustments, even if those transactions were
disregarded in the computation of the member’s income for the taxable year. See Part III, line 2 for more infor-
mation.
• 09 For 100% Wisconsin groups: Earnings and profits. A combined group member’s earnings and profits are
adjusted to reflect the undistributed earnings and profits of a subsidiary that is a member of the same combined
group. The provisions of 26 CFR 1.1502-33, and the regulations which it references, shall apply in determining
earnings and profits as if the Wisconsin combined group is a federal consolidated group. Undistributed earnings
and profits attributed to a subsidiary of a combined group member from any lower-tier subsidiary may not be
included in the combined group member's earnings and profits or its subsidiary's earnings and profits except to
the extent the lower-tier subsidiary's earnings and profits are attributable to net income that was or would have
been, included in the group's combined unitary income. Intercompany interest and other expenses are included
in these adjustments, even if those transactions were disregarded in the computation of the member’s income
for the taxable year. See Part III, line 2 for more information.
• 10 Moving expenses, as defined in sec. 71.01 (8j), Wis. Stats., paid or incurred during the taxable year to move
the taxpayer’s Wisconsin business operation, in whole or in part, to a location outside the state or to move the
taxpayer’s business operations outside the United States may not be deducted as provided under the IRC.
• 11 Entity-Level Tax Election Made by a Partnership – If the corporation is a partner in a partnership that makes
the entity level tax election, make an adjustment to remove the items of income, gain, loss, or deduction that
were included in federal taxable income before net operating loss and special deductions. If the partnership
makes the election, the box on Schedule 3K-1, Part C, box 3 will be checked. Include a copy of the Schedule
3K-1 and all supplemental schedules with the return.

Subtractions from Income

Line 4a. Wisconsin Subtraction Modification for Dividends – Enter the total from line 4 of Form 6Y. See the Form
6Y instructions for an explanation of dividends that are eligible for the subtraction.
Line 4b. Related Entity Expenses – If the combined group made an addition modification for related entity expenses
on Form 6, Part II, line 2c, this is where the amount that qualifies for a deduction is reported. Enter the amount of the
expenses from Form 6, Part II, line 2c, that are deductible using the criteria described in Conditions for Deducting
Related Entity Expenses, below.
For corporations that are partners, members, or beneficiaries of pass-through entities, also include the amount of
allowable related entity expense reported on line 22b of Schedule 3K-1 and on line 14b of Schedule 2K-1, as appli-
cable.
Conditions for Deducting Related Entity Expenses. Section 71.80(23)(a)3., Wis. Stats., provides that a related
entity expense that was added back on Form 6, Part II, line 2c, qualifies for a deduction if all of the following conditions
are met:

IC-506 (R. 12-24) 37

- 38 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• The primary motivation for the transaction was one or more business purposes other than the avoidance or
reduction of state income or franchise taxes;
• The transaction changed the economic position of the taxpayer in a meaningful way apart from tax effects; and
• The expenses were paid, accrued, or incurred using terms that reflect an arm’s length relationship.
Factors that may indicate that the expense does not qualify for a deduction include the following:
• There was no actual transfer of funds from the taxpayer to the related entity, or the funds were substantially
returned to the taxpayer, either directly or indirectly.
• If the transaction was entered on the advice of a tax advisor, the advisor’s fee was determined by reference to
the tax savings.
• The related entity does not regularly engage in similar transactions with unrelated parties on terms substantially
similar to those of the subject transaction.
• The transaction was not entered into at terms comparable to arm’s length as determined by Treas. Reg. 1.482-
1(b).
• There was no realistic expectation of profit from the transaction apart from the tax benefits.
• The transaction resulted in improper matching of income and expenses.
• An expense for the transaction was accrued under FIN 48.
The statutes (sec. 71.80(23)(a)1. and 2., Wis. Stats.) provide some additional conditions under which a related entity
expense may qualify for a deduction, subject to some important exceptions. Those conditions are:
• If the expense was paid to a related entity that is merely acting as a conduit between the taxpayer and an unre-
lated entity, or
• If the related entity was subject to a tax measured by net income or receipts and the net income or receipts of
the transaction were included in its tax base.
More Information on Related Entity Expenses. For more information on the deductibility of related entity expenses,
see the Schedule RT instructions. Even if Schedule RT is not required the instructions to Schedule RT provide helpful
information regarding deductibility of related entity expenses.
Line 4c. Income from Related Entities Whose Expenses Were Disallowed – If any corporation in the combined
group has income from a related entity which paid, accrued, or incurred expenses to the corporation, and that related
entity could not deduct those expenses according to the instructions for line 4b, the corporation may subtract the
corresponding income from its taxable income.
To claim a subtraction on line 4c, the corporation must obtain Schedule RT-1 from the related entity and submit
Schedule RT-1 with Form 6. See the Schedule RT-1 instructions for further details.
Line 4d. Subpart F and Section 965(a) Income – Each combined group member enters the Subpart F income and
the Section 965(a) inclusion amount on Form 6, page 1, line 1. Subpart F income is reported on Form 1120, Schedule
C, line 16, column (a).
• Subpart F income is reported on Form 1120, Schedule C, line 16, column (a)
• Section 965(a) inclusion income is reported on federal Form 965
• Do not include Previously Taxed Earnings and Profits (PTEP) aka Previously Taxed Income (PTI) required to be
reported on Form 1120, Schedule M-1 or M-3, Reconciliation of Income (Loss) per Books with Income per Return
• PTEP/PTI is not netted against a Subpart F income subtraction
Line 4e. Global Intangible low-taxed income (GILTI) – Enter the GILTI amount included on Form 6, page 1, line
1. Each combined group member enters the amount required to be reported on Form 1120, Schedule C, line 17,
column (a).
Line 4f. Foreign Dividend Gross-Up – Enter the foreign dividend gross-up income included in the amount on Form
6, page 1, line 1. Each combined group member enters the amount required to be reported on Form 1120, Schedule
C, line 18, column (a).

Line 4g. Nontaxable Income – Enter nontaxable income included in computing federal taxable income. Include a
schedule with the return showing the payers and amounts of nontaxable income and explaining why that income isn’t
taxable.

IC-506 (R. 12-24) 38

- 39 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• Interest, dividends, and capital gains from the disposition of intangible assets are nontaxable if both of the follow-
ing are true: (1) The operations of the payer are not unitary with those of the payee, and (2) The payer and payee
are not related as parent company and subsidiary or affiliates and the investment activity from which the income
is received is not an integral part of a unitary business.
• Income may also be nontaxable under the principles of the U.S. Supreme Court decision in Allied-Signal v. Di-
rector, Div. of Taxation, 504 U.S. 768 (1992), if the investment is passive and does not serve an operational
function.
• For corporations subject to the Wisconsin income tax rather than the franchise tax, nontaxable income also in-
cludes interest on United States government obligations.
CAUTION: Expenses related to nontaxable income aren’t deductible and must be added to federal taxable income
on Form 6, Part II, line 2e. However this rule does not apply to IRC §265 expenses identified at sec. 71.26(3)(L), Wis.
Stats.
Line 4h. Foreign Taxes – Enter foreign taxes paid or accrued during the year not deducted in computing federal
taxable income and not included on Form 6, Part II, line 4f.
Line 4i. Cost Depletion – For taxable years beginning on or after January 1, 2014, Wisconsin allows percentage
depletion, so an adjustment is generally not required.
Line 4j. Basis, Section 179, and Depreciation Differences –
• Enter the amount by which the Wisconsin deduction for depreciation or amortization exceeds the federal deduc-
tion for depreciation or amortization. Provide a schedule showing the computation details. These differences can
happen because of IRC sections not adopted for Wisconsin purposes and electing a different depreciation
method under the IRC in effect for Wisconsin purposes. For further information about the differences between
federal and Wisconsin basis and depreciation, see the section titled Conformity with IRC and Exceptions in the
Form 6 instructions, as applicable.
• If the total Wisconsin adjusted basis is less than total federal adjusted basis, see the instructions for Form 6, Part
II, line 2f.
Line 4k. Amount by Which the Wisconsin Basis of Assets Disposed of Exceeds the Federal Basis - Enter the amount
by which the Wisconsin basis of assets disposed of exceeds the federal basis. See the instructions for Form 6, Part
II, line 2g, for an example. Provide a schedule showing the computation details.
Investment in a Wisconsin Qualified Opportunity Fund (QOF) – A corporation may qualify for a basis adjustment
under sec. 71.26(3)(vm), Wis. Stats., if all of the following conditions are met:
• In a previous year, the corporation deferred paying tax on a capital gain by investing in a Wisconsin QOF.
• For the year in which the corporation invested in the Wisconsin QOF, the Wisconsin QOF properly filed Wisconsin
Form WQOF and provided a copy to the corporation. Exception: Form WQOF is not required for taxable years
beginning prior to January 1, 2020.
• The corporation held the investment in the Wisconsin QOF for at least 5 years.
• For the taxable year beginning in 2023, the corporation qualifies for the federal exclusion under sec. 1400Z-
2(b)(2)(B)(iii), IRC, or sec. 1400Z-2(b)(2)(B)(iv), IRC.
If the above conditions are met, the corporation may use the following worksheet to calculate its subtraction.
Worksheet Amount
Line 1 – If the investment in the WI QOF was held for at least 5 years but less than 7
years, enter 10%. If the investment in the WI QOF was held for 7 years or more, enter
15%.
Line 2 – Amount of deferred gains from the investment in a WI QOF.
Line 3 – Multiply line 2 by line 1. This is the amount of the corporation's basis adjustment
to include on Form 6, Part II, Line 4k.

Line 4l. Federal Wage Credits – Enter wages not deductible in computing federal income because they are being
used in computing federal wage tax credits. For additional information, see page 8 of Wisconsin Tax Bulletin 214.
Line 4m. Federal Research Credit Expenses – Enter research expenses not deductible in computing federal in-
come because they are being used in computing the federal credit for increasing research activities.

IC-506 (R. 12-24) 39

- 40 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Line 4n. Other Subtractions – Enter any other subtractions to federal income that are not specifically listed in lines
4a-4m and 4o. Include the numerical code number in the space to the right of the letter. For example:

CAUTION: Do not enter subtractions on line 4n that are specifically designated on lines 4a-4m and 4o. For example,
if a depreciation adjustment is passed through from a partnership on Schedule 3K-1, enter the amount on line 4j,
not on line 4n.

Other Subtractions from federal income may include:
• 01 Adjustments required as a result of changes made to the IRC which don’t apply for Wisconsin .For Wisconsin,
the Internal Revenue Code means the federal IRC as amended to December 31, 2022, with exceptions. See
"Conformity with Internal Revenue Code and Exceptions" earlier in the instructions for a list of IRC provisions
adopted and not adopted.
• 02 Adjustments required as a result of making different elections for Wisconsin and federal purposes. For addi-
tional information, see page 8 of Wisconsin Tax Bulletin 214.
• 03 Separately stated items of expense and adjustments for differences between the federal and Wisconsin treat-
ment of any items of an S corporation that opts out of Wisconsin tax-option status.
• 04 For credit unions, an adjustment to remove income from non-public deposits from Wisconsin income as de-
scribed in the instructions to Schedule CU-1.
• 05 Other (include a statement detailing the source and amounts).
• 06 For 100% Wisconsin groups: Intercompany transactions (except those to which Treas. Reg. §1.1502-13 al-
ready applies) for expenses paid, accrued, or incurred by one member of the combined group to another, are
disregarded so that they neither increase nor decrease a member’s portion of the combined unitary income. This
does not apply to intercompany transactions which occurred in taxable years beginning before January 1, 2009
or to intercompany transactions where the income, expense, gain, or loss would not otherwise be subject to
combination. See Part III, line 2 for more information.
• 07 For 100% Wisconsin groups: Capital gains and losses. The net capital gain or loss, after applying any sharable
net capital loss carryover, is first determined for the combined group as a whole. If the result is a net capital gain
for the group, the net capital gain is assigned to the members that would have a net capital gain from the unitary
business if they were not members of the combined group, in proportion to the amount of that net capital gain. If
the result is a net capital loss for the group, the net capital loss is assigned to the members that would have a
net capital loss from the unitary business if they were not members of the combined group, in proportion to the
amount of that net capital loss. Then each member computes its net capital gain or loss from separate entity
items. See Part III, line 2 for more information.
• 08 For 100% Wisconsin groups: Basis adjustments. A combined group member’s basis in stock of a subsidiary
that is a member of the same combined group is adjusted to reflect the subsidiary's distributions and items of
income, gain, deduction, and loss taken into account while the subsidiary was a member of the combined group.
Intercompany interest and other expenses are included in these adjustments, even if those transactions were
disregarded in the computation of the member’s income for the taxable year. See Part III, line 2 for more infor-
mation.
• 09 For 100% Wisconsin groups: Earnings and profits. A combined group member’s earnings and profits are
adjusted to reflect the undistributed earnings and profits of a subsidiary that is a member of the same combined
group. The provisions of 26 CFR 1.1502-33, and the regulations which it references, shall apply in determining
earnings and profits as if the Wisconsin combined group is a federal consolidated group. Undistributed earnings
and profits attributed to a subsidiary of a combined group member from any lower-tier subsidiary may not be
included in the combined group member's earnings and profits or its subsidiary's earnings and profits except to
the extent the lower-tier subsidiary's earnings and profits are attributable to net income that was or would have
been, included in the group's combined unitary income. Intercompany interest and other expenses are included
in these adjustments, even if those transactions were disregarded in the computation of the member’s income
for the taxable year. See Part III, line 2 for more information.
• 10 The amount of net income from an out-of-state business performing disaster relief work. See Publication
411 – Disaster Relief, for more information.

IC-506 (R. 12-24) 40

- 41 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• 11 Entity-Level Tax Election Made by a Partnership – If the corporation is a partner in a partnership that makes
the entity level tax election, enter an adjustment to remove the items of income, gain, loss, or deduction that were
included in federal taxable income before net operating loss and special deductions. If the partnership makes
the election, the box on Schedule 3K-1, Part C, box 3 will be checked. Include a copy of the Schedule 3K-1 and
all supplemental schedules with the return.
• 12 Financial Institution Commercial Loan Exemption
Note: The income from the above programs is included in federal income per sec. 61, IRC (unless an exception
applies), and is excluded from Wisconsin gross income. Expenses paid for with these programs and deducted in the
computation of federal income are not required to be added back on the Wisconsin return.
Line 4o. Nontaxable Income from Life Insurance Operations – If any corporation in the combined group is an
insurance company that has both life insurance operations and non-life insurance operations, enter the amount of
nontaxable income from life insurance operations as computed on Form 6I, line 13. See the Form 6I instructions for
details.
Line 6. Total Nonapportionable and Separately Apportioned Income – Complete this line only if any member of
the group has nonapportionable income, items accounted for using separate accounting, or other income or loss that
cannot be included in combined unitary income. For example, this line may apply in cases where a combined group
member has income from the unitary business that is excluded from combined unitary income under the water’s edge
rules.
• If any member of the group has income or loss reportable on line 6 (often called income or loss from “separate
entity items”), prepare Form N for each applicable member and enter the total from line 8 of all Forms N.
• The total on line 6 is the taxable income excluded from the group’s combined unitary income. If any of this amount
is allocable or separately apportionable to Wisconsin, enter the Wisconsin amount on Form 6, Part III, line 4. See
the instructions to Form N for details.
Line 7a: Elimination adjustment for 100% Wisconsin Group Members - Complete this line only for members of
100% Wisconsin combined groups (if 100% apportionment is entered on Form 6, page 1, line 2). Enter each mem-
ber's elimination adjustment in their respective column. If a member does not have elimination adjustments, leave
the line blank.
Line 7b: Pre-apportioned income after elimination adjustments - Complete this line only for members of 100%
Wisconsin combined groups (if 100% apportionment is entered on Form 6, page 1, line 2). Subtract line 7a from line
7 for each member's column and enter the result here and on Form 6, Part III, line 2. If a member did not have an
elimination adjustment on line 7a, enter the amount from line 7 on line 7b, and enter the amount from line 7b on Form
6, Part III, line 2.

Part III: Member's Share of Form 6 Items

Enter the corporation's name and federal employer identification number. Enter as much of the corporation's name
that will fit in the space provided. The corporation's full name will be entered on Part VI of Form 6. If a foreign
company does not have a FEIN because they are not required to obtain one, the foreign company should
enter all 9's in the FEIN field.
Enter the information for each member in a separate column. If there are more than three members, use additional
pages 8 and 9 of Form 6. Once all members have been entered compute the combined total column for all the
members of the group.
For example, if there are seven members in the combined group, enter members one through three on pages 8 and
9 of Form 6, leaving the combined total column blank. Next, enter members four through six on pages 8 and 9 of
Form 6, leaving the combined total column blank. Finally, complete another page 8 and 9 of Form 6 for the seventh
and final member. Leave the other two columns blank and enter the combined total for all members of the group in
the final column.
Line 1a. Apportionment Numerator – Enter the amount from Schedule A-01, A-02, A-03, A-04, A-05, A-06, A-07,
A-08, A-09, A-10, or A-11. 100% Wisconsin groups should leave this line blank.
Line 1b. Apportionment Denominator – Enter the amount from Schedule A-01 to A-11. 100% Wisconsin groups
should leave this line blank.
Line 1c. Total Combined Apportionment Total –Enter the combined total from line 1b for all combined group
members and enter it on the line for each group member. 100% Wisconsin groups should leave this line blank.

IC-506 (R. 12-24) 41

- 42 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Line 1d. Apportionment Percentage – For each combined group member, divide the amount on line 1a by the
amount on line 1c. 100% Wisconsin groups should leave this line blank.
Enter the apportionment schedule each member used. For example, if Schedule A-01, Wisconsin Single Sales Factor
Apportionment Data for Nonspecialized Industries, was used by the first member, enter "01" in the members column.
Line 2. Members Share of Combined Unitary Income
• Non-100% Wisconsin Groups: For each member, multiply the amount on the combined total line from Form 6,
Part II, line 8 by the member's amount on line 1d.
• 100% Wisconsin Groups: For combined groups that are engaged in business solely in Wisconsin, and therefore
not eligible to use apportionment, each member’s net income subject to combination is determined on a separate
entity basis and then adjusted to reflect the member’s status as a combined group member. These incomes are
added together to arrive at the combined unitary income. Therefore, if some combined group members have net
income from the unitary business and others in the same group have net loss from the unitary business, the
combined group’s tax liability is based on the total aggregate net income or loss of the unitary business.
• Do not multiply Part II, line 8 by Part III, line 1d. Since a 100% Wisconsin group does not use apportionment,
the amount on each member’s line 2 should equal the member's amount from Part II, line 7b; however, the
corporation must make the adjustments prescribed in sec. Tax 2.61(8), Wisconsin Administrative Code, to reflect
the corporation’s status as a combined group member. To make those adjustments, complete Part II lines 2j
and/or 4n as appropriate. See the instructions for Part II lines 2j and 4n for further information.
The following adjustments are required under sec. Tax 2.61(8), Wisconsin Administrative Code:
• Intercompany transactions (except those to which Treasury Reg. §1.1502-13 already applies) for expenses
paid, accrued, or incurred by one member of the combined group to another, are disregarded so that they neither
increase nor decrease a member’s portion of the combined unitary income. This does not apply to
intercompany transactions which occurred in taxable years beginning before January 1, 2009 or to intercompany
transactions where the income, expense, gain, or loss would not otherwise be subject to combination.
• Capital gains and losses. The net capital gain or loss, after applying any sharable net capital loss carryover, is
first determined for the combined group as a whole. If the result is a net capital gain for the group, the net capital
gain is assigned to the members that would have a net capital gain from the unitary business if they were not
members of the combined group, in proportion to the amount of that net capital gain.
If the result is a net capital loss for the group, the net capital loss is assigned to the members that would have a
net capital loss from the unitary business if they were not members of the combined group, in proportion to the
amount of that net capital loss. Then each member computes its net capital gain or loss from separate entity
items.
• Basis adjustments. A combined group member’s basis in stock of a subsidiary that is a member of the same
combined group is adjusted to reflect the subsidiary's distributions and items of income, gain, deduction, and loss
taken into account while the subsidiary was a member of the combined group. Intercompany interest and other
expenses are included in these adjustments, even if those transactions were disregarded in the computation of
the member’s income for the taxable year.
• Earnings and profits. A combined group member’s earnings and profits are adjusted to reflect the undistributed
earnings and profits of a subsidiary that is a member of the same combined group. The provisions of 26 CFR
1.1502-33, and the regulations which it references, shall apply in determining earnings and profits as if the Wis-
consin combined group is a federal consolidated group. Undistributed earnings and profits attributed to a sub-
sidiary of a combined group member from any lower-tier subsidiary may not be included in the combined group
member's earnings and profits or its subsidiary's earnings and profits except to the extent the lower-tier subsidi-
ary's earnings and profits are attributable to net income that was or would have been, included in the group's
combined unitary income. Intercompany interest and other expenses are included in these adjustments, even if
those transactions were disregarded in the computation of the member’s income for the taxable year.
After making the adjustments above, if there are some members with net income from the unitary business and others
with net losses from the unitary business, do not make any adjustments on line 2 to offset the losses against the
incomes. Those adjustments will be accounted for on line 3.
Line 3. Adjustment for Current Year Loss Offset – Complete this line if the combined group is a 100% Wisconsin
group and there are some members with net income from the unitary business and others with net loss from the
unitary business, as computed on line 2.
• Skip line 3 if all members have a positive amount on line 2 or if all members have a negative amount on line 2.

IC-506 (R. 12-24) 42

- 43 -

Enlarge image

                                  2024 Form 6 Instructions for Combined Returns 
 
• A member’s positive amount (income) on Line 2 must be offset by other members’ negative amounts (losses) on 
  Line 2. Line 3 is used to account for these offsets for purposes of computing the member’s gross tax and ac-
  counting for net business losses. 
The computation of the amount on line 3 depends on whether the combined unitary income reported on Form 6, Part 
II, line 8 is a positive amount (income) or a negative amount (loss). 
• If combined unitary income is positive, compute the total of the members’ negative amounts reported on line 2, 
  and allocate that total to the members with positive amounts on line 2 in proportion to those positive amounts. If 
  combined unitary income is negative, compute the total of the members’ positive amounts reported on line 2, and 
  allocate that total to the members with negative amounts on line 2 in proportion to those negative amounts. 
• If offset amounts are computed, the allocation method described above must be used. On line 3, report the ad-
  justments to each member’s amount on line 2 as necessary to reflect the offset. 
The following examples illustrate how to determine the adjustment amounts to enter on line 3: 
Example 1: Combined Group ABCD consists of Member A, Member B, Member C, and Member D. The members’ 
amounts on line 2 are as follows: 
                  Form 6,Part III   A                    B            C           D 
                   Line 2:          10,000   30,000                   -15,000     -10,000 
                                                                                                                
As a whole, Group ABCD has combined unitary income of $15,000 = ($10,000 + $30,000 - $15,000 - $10,000), which 
is reported on Form 6, Part II, line 8. This amount consists of a total of $40,000 of income from Members A and B 
and a total of -$25,000 of loss from Members C and D. The loss amount from Members C and D is allocated to 
Members A and B on a pro rata basis in proportion to their income amounts on line 2. Thus, the amount of loss 
allocated to Member A is -$6,250 = $10,000/(40,000 x -$25,000) and the amount allocated to Member B is -$18,750 
= $30,000/(40,000 x -$25,000). 
Therefore, the amounts reported by each member on Form 6, Part III, lines 2 and 3 are as follows: 
                  Form 6,Part III   A                    B            C           D 
                   Line 2:          10,000   30,000                   -15,000     -10,000 
                   Line 3:          -6,250   -18,750                    15,000     10,000 
                                    3,750    11,250                   0           0 
 
After the allocation, C and D have $0 of the combined unitary income and A and B have the entire $15,000 the group’s 
combined unitary income. 
 
Example 2: Assume the same facts as Example 1, except that Member A reports $15,000 on line 2 and Member B 
reports $5,000 on line 2, so the amounts are as follows: 
                  Form 6,Part III   A                    B            C           D 
                   Line 2:          15,000   5,000                    -15,000     -10,000 
 
As a whole, Group ABCD has a combined unitary loss of -$5,000 (= $15,000 + $5,000 - $15,000 - $10,000), which 
is reported on Form 6, Part II, line 8. This amount consists of a total of $20,000 of income from Members A and B 
and a total of -$25,000 of loss from Members C and D. The income amount from Members A and B is allocated to 
Members C and D on a pro rata basis in proportion to their loss amounts on line 2. Thus, the amount of income 
allocated to Member C is $12,000 = -$15,000/(-$25,000 x $20,000) and the amount allocated to Member D is $8,000 
= -$10,000/(-$25,000 x $20,000). 
Therefore, the amounts reported by each member on lines 2 and 3 are as follows: 
                  Form 6,Part III   A                    B            C           D 
                   Line 2:          15,000   5,000                    -15,000     -10,000 
                   Line 3:          -15,000       -5,000                12,000     8,000 
                   Total            0                  0              -3,000      -2,000 
 
Note that after the allocation, A and B have $0 of the combined unitary loss and C and D -$5,000 of the group’s 

IC-506 (R. 12-24)                                        43

- 44 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

combined unitary loss.
For combined groups that are not 100% Wisconsin groups and use the apportionment method to compute income, if
a member has a negative apportionment factor which results in negative apportionable income on line 2, the member
is required to enter the amount from line 2 on line 3 as a positive value to offset the negative value on line 2.
For combined groups that are not 100% Wisconsin groups and use the apportionment method to compute income, if
the numerator of a member's modified sales factor is a positive number and the denominator is a negative number
or zero, the combined unitary income shall be apportioned to the member. The member's separate company denom-
inator has no effect on this determination. If this results in apportioning all of the combined unitary income to more
than one member, the combined unitary income is apportioned to the members having positive modified sales factor
numerators in proportion to the amounts of their numerators. See example below.

Line 4. Wisconsin Net Nonapportionable and Separately Apportioned Income – If any member has net income
or loss not included in combined unitary income, complete Form N to determine the amount of Wisconsin income (if
any). Enter the amount from Form N, line 14 on line 4.
Line 5. Net Capital Loss Adjustment – If the combined group reported a net capital gain on Form 6, Part I, line 30,
and any member has non-sharable capital loss carryovers or a current year net capital loss from Form N, complete
Form 6CL to determine the amount of additional capital loss allowable to that member. On line 5, enter the amount
from the corporation’s Form 6CL, Part I, line 9e. See the Form 6CL instructions for details.
Line 6. Loss Adjustment for Insurance Companies – If the corporation is an insurance company and the sum of
lines 2 through 4 minus line 5 is a negative amount, reduce the loss amount by the dividends received deduction.
See the Form 6I instructions for details. If the corporation has an amount on Form 6I, line 24, enter that amount on
line 6.
Line 7. Net Business Loss Carryforward – If the sum of lines 2 through 4 minus line 5 is a positive amount and the
corporation has a net business loss carryforward, see the instructions for Form 6, Part IV. Enter the amount from
Form 6, Part IV, line 18.
Line 8. Wisconsin Net Income:
• If a member did not check the box for excess inclusion income from a real estate mortgage investment
conduit, compute Wisconsin net income as provided below.
Line 2: Members share of combined income
+ Line 3: Adjustment for current year loss offset
+ Line 4: Nonapportionable and separately apportioned
- Line 5: Net capital loss adjustment
+ Line 6: Loss adjustment for insurance companies
- Line 7: Net business loss carryforward
Wisconsin Net Income
• If a member checked the box for excess inclusion income from a real estate mortgage investment conduit,
compute the amount to enter on line 8 for each member that checked the box using the worksheet below:
Real Estate Mortgage Investment Conduit Excess Inclusion Income Computation (compute a separate worksheet for
each member that checked the box on line 8):
1. Enter the member's excess inclusion income from federal
Schedule Q (Form 1066) for the taxable year 1. _________________
2. Enter the member's apportionment percentage from Form 6, Part III, line 1d 2.__ __ __ .__ __ __ __%

IC-506 (R. 12-24) 44

- 45 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

3. Multiply line 1 by line 2 3. _________________
4. Enter the member's amount from Form 6, Part III, line 8; however,
if the amount is a loss, enter 0 4. _________________
• If line 4 is greater than line 3, there is no excess inclusion income adjustment required.
• If line 4 is less than line 3, enter the amount from line 3 on Form 6, Part III, line 8 and check the box below
the line.
Line 9. Gross Tax – For corporations other than insurance companies, the gross tax on line 9 is computed as follows:
Share of combined unitary income (= line 2 + 3)
+ Income from separate entity items (line 4)
- Net capital loss adjustment (line 5)
- Net business loss carryforward (line 7)
Wisconsin net income
x 7.9% (0.079)
= Gross tax (line 9) (Cannot be less than zero)
Line 9 Computation for Insurance Companies. For insurance companies, the gross tax on line 9 is generally the
lesser of the amount computed for regular corporations, as shown above, or 2% of its gross premiums. An insurance
company completes Form 6I, Part IV to determine its gross tax. For an insurance company, the amount to enter on
Form 6, Part III, line 9 is the lesser of the amounts on Form 6I, line 26 or line 29.
Line 10. Nonrefundable Credits – If the corporation has nonrefundable credits to use against its gross tax, or re-
search credits eligible to be shared with the other combined group members, see the instructions for Form 6, Part V.
Enter the amount from Form 6, Part V, line 6.
Line 11. Economic Development Surcharge – The economic development surcharge is computed separately for
each member based on each member's activities reported on Form 6, Part III. If one member of the combined group
has nexus with Wisconsin, all members of the combined group are considered to have nexus with Wisconsin for
purposes of the economic development surcharge. However, only members that have “gross receipts from all activi-
ties” of $4 million or more during the taxable year are subject to the economic development surcharge.
• Gross Receipts for Purposes of Economic Development Surcharge. The gross receipts for purposes of
applying the $4 million threshold comes from Form 6, Part VI, line 6. See sec. Tax 2.32, Wisconsin Administrative
Code and the instructions for Form 6, Part VI, line 6 for the definition of “Gross Receipts from All Activities".
• Computation of Surcharge. If the corporation’s gross receipts from all activities on line 11a are $4 million or
more, multiply the gross tax on line 11b by 3% and enter the result on line 11c, except if the result is less than
$25, enter $25, and if the result is greater than $9,800, enter $9,800.
If the corporation is simultaneously included in more than one return (for example, if the corporation is a member of
another combined group), the economic development surcharge can apply only once for the corporation’s entire
gross tax for its taxable year.
For more information about the economic development surcharge, refer to Publication 400, Wisconsin’s Economic
Development Surcharge, which is available on the department’s web site at reve-
nue.wi.gov/Pages/HTML/taxpubs.aspx#other. Also, for additional information and examples relating to the economic
development surcharge for combined group members, see sec. Tax 2.82(5) and (6), Wisconsin Administrative Code.
Line 12. Wisconsin Tax Withheld – Enter the corporation’s Wisconsin tax withheld from pass-through entities, as
reported on Wisconsin Schedules 3K-1 or 2K-1. include a copy of the Schedule 3K-1 or 2K-1 with the combined
return. Also enter the amount of Wisconsin tax withheld from lottery prizes.
If this is an amended return, enter the Wisconsin tax withheld reported on the original Form 6, unless the amount
originally reported was incorrect.
Line 13. Refundable Credits –Report each member's refundable credits. In the space next to the line, enter the 2-
digit code corresponding to each refundable credit from the table below, and the amount of credit for each code listed.
Any refundable credits in excess of the combined group’s tax liability will be refunded to the designated agent.
Most credits must be computed on a department-prescribed schedule. The table indicates the schedule that must be
used by each member to compute the credit and the line number of that schedule that shows the total available credit.
The applicable credit schedule(s) must be included with the combined return.

IC-506 (R. 12-24) 45

- 46 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Codes for Refundable Credits

Credit Code Schedule Line

Business development credit 62 BD 3

Electronics and Information Technology Manufacturing Zone Credit 63 EIT 5

Enterprise zone jobs credit 52 EC 3
FC 17
Farmland preservation credit 53

Farmland preservation credit 61 FC-A 13

25% Refundable portion of research credit 64 R 20

Note: Combined groups should not file Schedule CR to summarize their credits. The credit codes on Form
6, Part III, line 13 replace Schedule CR.
For information on how to qualify for credits, see Publication 123, Business Tax Incentives (available on the Depart-
ment of Revenue’s web site at revenue.wi.gov/Pages/HTML/taxpubs.aspx#business). The instructions to each credit
schedule may also provide helpful information. These schedules and instructions are on the department’s web site
at revenue.wi.gov/Pages/HTML/formpub.aspx.

Part IV: Wisconsin Net Business Loss Carryforward

Enter the corporation's name and federal employer identification number. Enter as much of the corporation's name
that will fit in the space provided. The corporation's name will be entered on Part VI of Form 6. If a foreign company
does not have a FEIN because they are not required to obtain one, the foreign company should enter all 9's
in the FEIN field.
Enter the information for each member in a separate column. If there are more than three members, use additional
pages 9 and 10 of Form 6. Once all members have been entered, compute one combined total column for all the
members of the group.
For example, if there are seven members in the combined group, enter members one through three on pages 9 and
10 of Form 6, leaving the combined total column blank. Next, enter members four through six on pages 9 and 10 of
Form 6, leaving the combined total columns blank. Finally, complete another page 9 and 10 of Form 6 for the seventh
and final member. Leave the other two columns blank and enter the combined totals for all members of the group in
the final column.
If any member will be using any net business loss carryforwards in this return, Form 6, Part IV must be completed to
ensure that non-sharable loss carryforwards and sharable loss carryforwards are calculated correctly.
Combined group members must use business loss carryforwards in a specific order. A combined group member shall
apply Net business loss (NBL) carryforwards are applied as incurred chronologically in the following order:
1. For 100% Wisconsin combined groups only: sharing of current year unitary losses;
2. Its own pre-2009 NBL carryforward to offset its own Wisconsin net income from separate entity items;
3. Its own pre-2009 NBL carryforward to offset its share of the Wisconsin combined group's Wisconsin income;
4. Its own post-2008 sharable NBL carryforward to offset its share of the Wisconsin combined group's Wisconsin
income;
5. Its share of post-2008 sharable NBL carryforward from other combined group members to offset its share of the
Wisconsin combined group's Wisconsin income;
6. Its share of sharable pre-2009 NBL carryforward from other combined group members up to the allowable 5%
amount to offset its share of the Wisconsin combined group's Wisconsin income.
See the common question, "Net Business Losses for Combined Groups" available at:
revenue.wi.gov/Pages/FAQS/ise-combrptd.aspx for further information.

IC-506 (R. 12-24) 46

- 47 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Line 1. Member's Portion of Combined Unitary Income – Enter the amounts from Form 6, Part III, lines 2 plus 3.
Line 2. Member's Net Nonapportionable Income – Enter the amount from Form 6, Part III, line 4.
Line 4. Member's Capital Loss Adjustment – Enter the amount from Form 6, Part III, line 5 as a positive number.
Line 6. Available Non-sharable Net Business Loss Carryforward – Enter the amount from Form 6BL, line 30,
column (i) the member elects to use to offset current year income. The total available non-sharable net business loss
carryforward is not required to be used. For example, the member may choose to use less nonsharable net
business loss carryforward on line 6 in order to use a credit that may be expiring. See the Tax Releases in
Wisconsin Tax Bulletin issues 138 (April 2004), 139 (July 2004), and 196 (January 2017) for more details on using
carryforwards of net business losses and credits. Wisconsin Tax Bulletins are on the department’s web site at reve-
nue.wi.gov/Pages/ISE/wtb-Home.aspx.
Line 7. Nonsharable Net Business Loss Carryforward Used – This is the amount of nonsharable net business
loss carryforward being used to offset the member's own income.
Line 9. Available Sharable Net Business Loss Carryforward – Enter the amount from Form 6BL, line 30, columns
(j) and (k) the member elects to use to offset current year income.
Line 10. Sharable Net Business Loss Carryforward Used – This is the amount of sharable net business loss
carryforward being used to offset the member's own income. This does not include any amounts that are being
shared with other combined group members. The amount of sharable net business loss carryforward being shared
with other combined group members is reported on line 13.
Line 11. Remaining Sharable Net Business Loss Carryforward – This is the amount of sharable net business
loss carryforward eligible to be shared with other combined group members to offset their remaining current year
combined unitary income.
Caution: Combined group members are not required to share any remaining shareable net business loss carryfor-
ward. However, the remaining sharable net business loss carryforward amounts from each combined group member
electing to share must be aggregated in order to calculate lines 13 and 14 of Form 6, Part IV.
Line 12. Remaining Income – This is the remaining income not offset by the member's non-sharable or shareable
net business loss carryforward.
Caution: The remaining income amounts for each combined group member are aggregated in order to calculate
lines 13 and 14 of Form 6, Part IV. However, net business loss carryforwards may not be shared with any combined
group member whose remaining income on line 12 is zero or less.
Line 13. Shareable Net Business Loss Carryforward Amount Being Shared With Other Members – Enter the
amount of the shareable net business loss each member is sharing with other combined group members. See the
examples for the calculation. The sum of all member's line 13 amounts should equal the sum of all member's line 14
amounts.
Note: The combined group member’s Form 6BL, columns (f), (g), and (h) should include the amount being shared
with other combined group members since this amount of shareable net business loss is being used up.
Line 14. Shareable Net Business Loss Carryforward Amount Being Shared With This Member – Enter the
amount of the shareable net business loss being shared with this member. See the examples for the calculation. The
sum of all member's line 13 amounts should equal the sum of all member's line 14 amounts.
The following examples illustrate how to determine the shareable net business loss carryforward amounts being
shared with other members of the combined group:
Example 1: Combined Group ABCD consists of Member A, Member B, Member C, and Member D. The combined
group members’ remaining shareable net business loss carryforward amounts and remaining income amounts for
2024 are as follows:
Form 6,Part IV A B C D
Line 11 24,000 16,000 0 0
Line 12 0 0 20,000 5,000

Member A and Member B have no remaining income and have offset all of their own income with their own non-
shareable and shareable net business loss carryforward amounts. Member C and Member D still have remaining

IC-506 (R. 12-24) 47

- 48 -

Enlarge image

                                2024 Form 6 Instructions for Combined Returns 
 
income after using their own non-shareable and shareable net business loss carryforward amounts. 
The amount of shareable net business loss carryforwards being shared between the combined group members are 
as follows: 
            Form 6, Part IV     A             B                         C                   D 
            Line 13             15,000        10,000                    0                   0 
            Line 14             0             0                  20,000                  5,000 
 
Line 13 calculation: Member A calculates $15,000 for line 13 (($24,000/$40,000) x $25,000 aggregate remaining 
income amount) and Member B calculates $10,000 for line 13 (($16,000/$40,000) x $25,000 aggregate remaining 
income amount). 
• The shareable net business loss carryforward amounts being shared with other combined group members must 
  be calculated on a prorated basis. The prorated basis is  the taxpayer's own remaining shareable net business 
  loss amount divided by the aggregate remaining shareable net business loss amount. This amount is then mul-
  tiplied by the lesser of the aggregate shareable net business loss carryforward amount or the aggregate remain-
  ing income amount. 
• After the aggregate shareable net business loss is shared with the other combined group members, the remaining 
  aggregate shareable net business loss is $15,000 ($40,000 - $25,000). The remaining shareable net business 
  loss amounts remain an attribute of the corporation that originally incurred the loss. At the end of 2024, Member 
  A would have a $9,000 ($24,000 - $15,000) shareable net business loss carryforward and Member B would have 
  a $6,000 ($16,000 - $10,000) shareable net business loss carryforward. 
Line 14 calculation: Member C calculates $20,000 for line 14 (($20,000/$25,000) x $25,000 aggregate remaining 
income amount) and Member D calculates $5,000 for line 14 (($5,000/$25,000) x $25,000 aggregate remaining in-
come amount). 
• The amount of shareable net business loss carryforward being used by each member must be calculated on a 
  prorated basis. The prorated basis is the taxpayer's own remaining income amount divided by the aggregate 
  remaining income amount. This amount is then multiplied by the lesser of the aggregate shareable net business 
  loss carryforward amount or the aggregate remaining income amount. 
• Since Member C and Member D only have $25,000 of aggregate remaining income and $40,000 of aggregate 
  remaining shareable net business loss carryforward is available, all of the income of Member C and Member D 
  has been offset. 
   
Example 2: Combined Group ABCD consists of Member A, Member B, Member C, and Member D. The combined 
group members’ remaining shareable net business loss carryforward amounts and remaining income amounts for 
2024 are as follows: 
 Form 6, Part IV        A              B             C                        D 
 Line 11                24,000    16,000             0                        0 
 Line 12                0              0             27,000                   20,000 
 
Member A and Member B have no remaining income and have offset all of their own income with their own non-
shareable and shareable net business loss carryforward amounts. Member C and Member D still have remaining 
income after using their own non-shareable and shareable net business loss carryforward amounts. 
The amount of shareable net business loss carryforwards being shared between the combined group members are 
as follows: 
 Form 6, Part IV        A              B             C                        D 
 Line 13                24,000         16,000        0                        0 
 Line 14                0              0             22,979                   17,021 
 
Line 13 calculation: Member A calculates $24,000 for line 13 (($24,000/$40,000) x $40,000 aggregate shareable net 
business loss amount) and Member B calculates $16,000 for line 13 (($16,000/$40,000) x $40,000 aggregate share-
able net business loss amount). 
• The shareable net business loss carryforward amounts being shared with other combined group members must 
  be calculated on a prorated basis. The prorated basis is the taxpayer's own remaining shareable net business 

IC-506 (R. 12-24)                             48

- 49 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

loss amount divided by the aggregate remaining shareable net business loss amount. This amount is then mul-
tiplied by the lesser of the aggregate shareable net business loss carryforward amount or the aggregate remain-
ing income amount.
• After the aggregate shareable net business loss is shared with the other combined group members, the remaining
aggregate shareable net business loss is $0 ($40,000 - $40,000). The remaining shareable net business loss
amounts remain an attribute of the corporation that originally incurred the loss. At the end of 2024, Member A
would have $0 ($24,000 - $24,000) and Member B would have $0 ($16,000 - $16,000) shareable net business
loss carryforwards.
Line 14 calculation: Member C calculates $22,979 for line 14 (($27,000/$47,000) x $40,000 aggregate shareable net
business loss amount) and Member D calculates $17,021 for line 14 (($20,000/$47,000) x $40,000 aggregate share-
able net business loss amount).
• The amount of shareable net business loss carryforward being used by each member must be calculated on a
prorated basis. The prorated basis is the taxpayer's own remaining income amount divided by the aggregate
remaining income amount. This amount is then multiplied by the lesser of the aggregate shareable net business
loss carryforward amount or the aggregate remaining income amount
• For tax year 2024, Member C would have taxable income of $4,021 ($27,000 - $22,979) and Member D would
have taxable income of $2,979 ($20,000 - $17,021)
Line 15. Remaining Income – This is the remaining income not offset by the member's own nonshareable or share-
able loss carryforward, or the shareable net business loss carryforwards from other members. Each member's re-
maining income amounts shall be aggregated in order to calculate lines 16 and 17.
Line 16. Pre-2009 Net Business Loss Carryforward Amount Being Shared with Other Members
If a member has unused net business loss carryforwards incurred in taxable years beginning before January 1, 2009,
the pre-2009 net business loss carryforwards not used by the member prior to the taxable year beginning on or after
January 1, 2012, may be shared up to five percent per year with other combined group members in taxable years
beginning on or after January 1, 2012, and before January 1, 2032.
The pre-2009 net business loss carryforward is a one-time computation. It is a member's total net business loss
carryforward as of the beginning of the first taxable year that begins after December 31, 2008, and not used by the
member in any taxable year beginning before January 1, 2012.
The pre-2009 net business loss carryforward is determined in Step 1 on page 9 of the 2012 Form 4M instructions.
Step 1: Determine the maximum amount in each year for this member that can be converted from nonshareable to
shareable and be shared with other members in that taxable year.

Line A Enter the amount from line F from page 9 of the 2012 Form 4M instructions. A. _____________
Line B Maximum percentage allowed to be shared per taxable year (5%) B. 0.05
Line C Multiply line A by line B. Round to the dollar. C. _____________
Line D Enter the member's taxable year beginning date from Form 6, Part VI, line 2. D. _____________
Line E Enter the member's taxable year ending date from Form 6, Part VI, line 2. E. _____________
Line F Number of days between dates on lines D and E. Do not enter more
than 365 days. For example, the number of days between February 14
and February 19 is 5 days. F. _____________
Line G Tentative maximum amounts that this member may share with other
Members for this taxable year. Multiply line C by (line F divided by
365). Round to the dollar. G. _____________
Line H Enter the amount of nonshareable net business loss that the
member is using from its Form 6, Part IV, line 7. H. _____________
Line I Maximum amount that this member may share with other members
for this taxable year.
Subtract line H from line A.
• If the difference is greater to or equal to line G, enter the amount from
line G and go to line J.

IC-506 (R. 12-24) 49

- 50 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

• If the difference is greater than zero but less than line G, enter the
difference and go to line J.
• If the difference is zero or less, enter zero and stop. There are no
remaining nonshareable net business loss carryforwards available. I.______________
Line J Does the member choose to share less than the maximum amount allowed
to be shared this year from line I? If yes, enter that amount here. This amount
must be between zero and equal to line I. If no, enter the amount from line I J. ______________
Step 2: Allocate to other members. Using the allocation method shown in the instructions for line 14, Examples 1
and 2, allocate the amounts (line J) being shared with other members. After this allocation has been made, enter the
member's amount shared with other members on Form 6, Part IV, line 16.
• The sum of all group members line 16 amounts should equal the sum of all group members line 17 amounts.
• The member's Form 6BL, columns (f), (g), and (h) should include the amounts that the member is sharing with
other members since this amount is being used up.
Step 3: Compute carryforward, if any. If the member did not use the maximum amount (line I) to offset the income of
other members, the remainder may be added to that portion of the pre-2009 net business loss carryforward that may
offset the income of all other members in a subsequent year until the pre-2009 net business loss carryforward is
completely used or expired. Pre-2009 net business loss carryforwards may not be used in any taxable year that
begins on or after January 1, 2032.
Line K Enter the amount from line I. K. ______________
Line L Enter the amount from Form 6, Part IV, line 16. L. ______________
Line M Subtract line L from line K. This amount may be carried forward. M. ______________
The member's Form 6BL, column (f) should include the amount that the member is converting to the new class of
pre-2009 shareable net business loss carryforward. In addition, this amount will be added to the member's Form 6BL,
column (k) for the subsequent taxable year.
Line 17. Pre-2009 Net Business Loss Carryforward Amount Being Shared With This Member – Enter the
amount of pre-2009 net business loss carryforward being shared with this combined group member. See the instruc-
tions for line 14, Examples 1 and 2, for the allocation method. The sum of all members' line 16 amounts should equal
the sum of all members' line 17 amounts.

Part V: Nonrefundable Credits

Enter the corporation's name and federal employer identification number. Enter as much of the corporation's name
that will fit in the space provided. The corporation's full name will be entered on Part VI of Form 6. If a foreign
company does not have a FEIN because they are not required to obtain one, the foreign company should
enter all 9's in the FEIN field.
Enter the information for each member in a separate column. If there are more than three members, use an additional
page 11 of Form 6. Once all members have been entered, compute one combined total column for all the members
of the group.
For example, if there are seven members in the combined group, enter members one through three on page 11 of
Form 6, leaving the combined total column blank. Next, enter members four through six on page 11 of Form 6, leaving
the combined total columns blank. Finally, complete another page 11 of Form 6 for the seventh and final member.
Leave the other two columns blank and enter the combined totals for all members of the group in the final column.
If the member is using nonrefundable credits, Part V must be completed to ensure that sharable credits and non-
sharable credits are properly accounted for.
Line 1. Available Nonrefundable Credits – Enter the total amount of available nonrefundable tax credits from the
credit schedules and Schedule CF.
• In the spaces to the left of the lines, enter the 2-digit code corresponding to each available credit from the table
below, and the total amount of available credit for each code listed. (Enter the credit code on the line that looks
like “ ”).
• Combined groups should not complete Schedule CR to summarize their credits. The credit codes on Form 6,
Part V replace Schedule CR.

IC-506 (R. 12-24) 50

- 51 -

Enlarge image

                                   2024 Form 6 Instructions for Combined Returns 
 
If credits are carried forward from prior years or there are current year unused credits that are being carried 
forward, complete a Schedule CF for each credit. 
Line 2. Gross Tax – Enter the member's gross tax from Form 6, Part III, line 9. 
Line 3. Summary of Nonrefundable Credits Used to Offset Tax –      In the spaces to the left of the lines, enter the 
2-digit code corresponding to each available credit from the table below, and the amount of credit the taxpayer is 
electing to use for each code listed. (Enter the credit code on the line that looks like “     ”). See Wisconsin Tax 
Bulletins 138 (April 2004), and 196 (January 2017) for more details on electing to use credits. 
• Most credits must be computed on a department-prescribed schedule. The table below indicates the schedule 
  that must be used to compute the credit and the line number of that schedule that shows the total available credit. 
  Only enter the amount of each credit the taxpayer is electing to use to offset the tax liability. The applicable credit 
  schedule(s) must be included with the combined return. 
• See Wisconsin Tax Bulletins   138 (April 2004),139 (July 2004) 178, (January 2013) 183,  (January 2014) , and 
  196 (January 2017) for more details on using carryforwards of credits and net business losses.       Wisconsin Tax 
  Bulletins  can  be  accessed  on  the  Department  of  Revenue’s  web  site  at revenue.wi.gov/Pages/ISE/wtb-
  Home.aspx. 
• Combined groups should not complete Schedule CR to summarize their credits. The credit codes on Form 6, 
  Part V replace Schedule CR. 
If credits from prior years are being used or current year unused credits are being carried forward, complete 
a Schedule CF for each credit type.  
Several nonrefundable credits expired for taxable years beginning on or after January 1, 2014. Those credits may no 
longer be computed; however, any eligible remaining carryover may be used until fully used or expired, whichever 
comes first. The credit schedule originally used to compute the credit is not completed for a carryforward of an expired 
credit. Instead, Schedule CF is completed for each credit that is being carried forward.  See the Schedule CF instruc-
tions for further details. When completing Form 6, Part V, line 3, use the credit codes from the table below, not the 
credit codes from the Schedule CF instructions. 
 
                                Codes for Nonrefundable Credits 
  Credit                                                                                   Code        Schedule 
  Agriculture credit                                                                       36          MA-A 
  Biodiesel fuel production credit: Carryforward                                           18          CF 
  Community development finance credit: unused carryover from prior years                  01          CF 
  Community rehabilitation program credit                                                  02          CM 
  Dairy and livestock farm investment credit: Carryforward                                 03          CF 
  Development opportunity zone investment credit:  unused carryover from prior years       35          CF 
  Development zones credit                                                                 04          DC 
  Development zone capital investment credit                                               37          DC 
  Early stage seed investment credit                                                       11          VC 
  Economic development credit                                                              12          ED 
  Electronic medical records credit: carryover                                             32          CF 
  Employee college savings account contribution credit                                     38          ES 
  Ethanol and biodiesel fuel pump credit: carryover                                        13          CF 
  Health insurance risk-sharing plan assessments credit                                    16          CF 
  Internet equipment credit: carryforward                                                  17          CF 
  Low-income housing tax credit                                                            39          LI 
  Manufacturer’s sales tax credit: carryforward                                            19          MS 
  Manufacturing investment credit: carryforward                                            20          MI 
  Manufacturing credit                                                                     34          MA-M 
  Postsecondary education credit: carryover                                                21          CF 

IC-506 (R. 12-24)                                      51

- 52 -

Enlarge image

2024 Form 6 Instructions for Combined Returns

Credit Code Schedule
Research expense credit 22 R
Research expense credit for activities related to certain energy efficient products 23 R
Research expense credit for activities related to internal combustion engines 24 R
Research facilities credit: carryover 25 CF
Research facilities credit for activities related to certain energy efficient products:
carryover 26 CF
Research facilities credit for activities related to internal combustion engines:
carryover 27 CF
Supplement to the federal historic rehabilitation credit 29 HR
Technology zone credit 30 CF
Veteran employment credit: carryover 33 CF
Water consumption credit: carryover 31 CF

Wisconsin law provides that the listed credits “may” be claimed for a taxable year. Because the statutes use the word
“may” instead of “shall” or “must”, the taxpayer has the option of claiming all, a portion, or none of the credit available
for a particular year. Any amount not used in the year for which a credit is computed may be carried forward and
offset against tax until entirely used or the 15-year carryforward period expires, whichever is earlier. For further infor-
mation see, Wisconsin Tax Bulletins 138 (April 2004) and 196 (January 2017). However, when claiming more than
one credit, the credits must be claimed in a specific order. See sec. 71.30(3), Wis. Stats. for the order.
For information on how to qualify for credits, see Publication 123, Business Tax Incentives (available on the Depart-
ment of Revenue’s web site at revenue.wi.gov/Pages/HTML/taxpubs.aspx). The instructions for each credit schedule
may also provide helpful information. These schedules and instructions can be found on the department’s web site
at revenue.wi.gov/Pages/HTML/formpub.aspx.
Line 4. Credit Used by Member – Subtract line 3e from line 2. This is the remaining tax after applying the credits..
Line 5. Sharing of Research Credits – If the available credits include one or more research credits, and those
credits are still available after the corporation accounts for the credits used on line 3e, the corporation may choose
to share the remaining research credits with the other combined group members.
Complete Form 6CS, Sharing of Research Credits, to determine the amount that may be shared. Enter the shared
amount on line 5. “Research credits” include:
• Nonrefundable research credits (Schedule R)
• Research facilities credit carryovers (Schedule CF)
• Development zones research credit carryforward (Schedule CF)
See the Form 6CS instructions for further details on sharing research credits.
Line 6. Total Nonrefundable Credits – Enter the amount from this line on Form 6, Part III, line 10.
CAUTION: The credits available for carryforward to 2025 must be reduced by the total amount on line 6.

Part VI: Additional Member Information

Enter the information for each member in a separate column. If there are more than three members, use additional
pages 12, 13, and 14 of Form 6. For example, if there are seven members in the combined group, enter members
one through three on pages 12, 13 and 14 of Form 6. Next, enter members four through six on additional pages 12,
13, and 14 of Form 6. Finally, complete a new page 12, 13, and 14 of Form 6 for the seventh and final member.
Enter the elimination adjustments for all members in the elimination adjustments column as positive and negative
values. A positive value will increase the total of the member's amounts reported in the combined total column and
a negative value will decrease the total of the member's amounts reported in the combined total column.
Line 1. State and Year of Incorporation – Enter the 2-letter postal abbreviation for the state (or name of the foreign
country) under whose laws the designated agent corporation is organized and the year of incorporation.
Line 2. Period Included in This Return – Enter the beginning and ending dates of the member’s taxable year
included in the combined return, even if they are the same beginning and ending dates as the combined group’s
taxable year.

IC-506 (R. 12-24) 52

- 53 -

Enlarge image

                                   2024 Form 6 Instructions for Combined Returns 
 
A combined group member using a different taxable year than the group itself, may convert to the combined group’s 
taxable year in one of two ways: 
• Preparing a separate income statement for the member for the months included in the combined group’s taxable 
  year.  
• Using the amounts for the member’s taxable year that ends during the combined group’s taxable year.  
• The designated agent must use the same method for all combined group members that have differing taxable 
  years, and the same method must be used each year. 
• If a member joined or left the combined group during the year, the beginning or ending date, or both, shown on 
  line 2 will be different than the beginning and ending dates of the combined group’s taxable year. 
• A member should only appear in one column of Form 6. If the member has two taxable periods due to filing two 
  short period returns, the information should be combined into one column and an attachment included with the 
  return detailing the computation of the amounts included in the column. 
For example, Member B files two short period returns – the first for the taxable period of January 1, 2024 through 
March 31, 2024 and the second for the taxable period of April 1, 2024 through December 31, 2024.  Member B should 
only be included in one column of Form 6.  The items of income, deduction, and credit for both periods should be 
combined into one column. For the taxable period on Form 6, Part VI, line 2, enter a beginning period of January 1, 
2024 and an ending period of December 31, 2024.  
Line 3. Member’s Taxable Year End – Enter the month and day of the corporation’s most recently ended taxable 
year, as determined for federal income tax purposes. If the corporation and the combined group have the same 
taxable year end, enter the month and day of the last day included in this return. 
Line 4. Extended Due Date – If the combined group has an extension of time to file its Wisconsin return, enter the 
extended due date. 
Disaster Relief Extension. If the return is filed under extension because of a federal or state disaster, include a 
statement indicating which disaster extension is being used and attach it to the  return. Additional information on 
disaster areas can be found here:  revenue.wi.gov/Pages/FAQS/pcs-extensn.aspx#ext5 
Line 5. Internal Revenue Service Adjustments – If a corporation’s federal tax return is adjusted by the IRS and the 
adjustments affect the Wisconsin net tax payable, the amount of a Wisconsin credit, a Wisconsin net business loss 
carryforward, or a Wisconsin capital loss carryforward, the adjustments must be reported to the Department of Rev-
enue within 180 days after they become final. 
File an amended return electronically by using one of the third-party software providers: 
revenue.wi.gov/Pages/OnlineServices/corp-partnership-third-party-vendors.aspx 
If an approved electronic filing waiver has been approved , send a copy of the final federal audit reports and any 
associated amended Wisconsin returns to the Wisconsin Department of Revenue, PO Box 8908, Madison, WI 53708-
8908.  
If submitting a federal audit report without an amended return, mail it to the Audit Bureau, Wisconsin Department of 
Revenue, Mail Stop 3-107, PO Box 8906, Madison, WI 53708-8906. Don’t include these items with the tax return for 
the current year. 
Line 6. Total Company Gross Receipts from All Activities – Enter the corporation’s total “gross receipts from all 
activities” as defined at sec. Tax 2.32(2)(a), Wisconsin Administrative Code. 
The taxable year used to determine this amount is the period included in the combined return, as identified on Form 
6, Part VI, line 2. 
The definition of Gross Receipts for the Economic Development Surcharge differs from the definition of Gross Sales 
for Apportionment as defined at sec. Tax 2.39(2)(c), Wisconsin Administrative Code. 
Economic Development Surcharge—Gross Receipts Defined 
 Gross  receipts  or  sales  reportable  on  federal  Form  Gross dividends reportable on federal Form 1120 
 1120, U. S. corporation income tax return 
 Gross interest income reportable on federal Form 1120  Gross rents reportable on federal Form 1120 

IC-506 (R. 12-24)                                  53

- 54 -

Enlarge image

                                 2024 Form 6 Instructions for Combined Returns 
 
 Gross receipts passed through from other entities, and  The gross sales price from the disposition of capital as-
 all other receipts that are included in gross income for  sets and business assets includable in computing the 
 Wisconsin franchise or income tax purposes.            net gain or loss on federal Form 1120 
 Gross royalties reportable on federal Form 1120         
 
Line 7. Wisconsin Sales – Enter the combined group members’ apportionment factor numerators from Form 6, Part 
III, line 1a. If the combined group member does not use apportionment, ignore this line. 
Line 8. Total Company Sales – Enter the combined group member's common apportionment factor denominator 
from Form 6, Part III, line 1b. If the combined group member doesn’t use apportionment, ignore this line. 
Line 9. Wisconsin Payroll – Enter the total amount of the combined group member's payroll located in Wisconsin. 
Include only amounts attributable to employees of the corporation. In the computation of payroll located in Wisconsin, 
include individuals that satisfy one or more of the following: 
• The individual’s service is performed entirely in Wisconsin.  
• The individual’s service is performed in and outside Wisconsin, but the service performed outside Wisconsin is 
  incidental to the individual’s service in Wisconsin.  
• A portion of the individual’s service is performed in Wisconsin and the base of operations of the individual is in 
  Wisconsin.  
• A portion of the individual’s service is performed in Wisconsin and, if there is no base of operations, the place 
  from which the individual’s service is directed or controlled is in Wisconsin.  
• A portion of the individual’s service is performed in Wisconsin and neither the base of operations of the individual 
  nor the place from which the service is directed or controlled is in any state in which some part of the service is 
  performed, but the individual’s residence is in Wisconsin.  
Line 10. Total Company  Payroll  – Enter the combined group member's  total  payroll everywhere. Include only 
amounts attributable to employees of the corporation. 
Line 11. Wisconsin Tangible Property – Enter the combined group member's end of year real and personal  prop-
erty cost basis located in Wisconsin. Do not include rented property. 
Line 12. Total Company Property – Enter the total combined group member's end of year real and personal property 
cost basis located everywhere. Do not include rented property.  
Line 13. Total Assets – Enter the combined group member's total company assets reported on the federal return. If 
the federal return is a consolidated return, enter the total company assets for this corporation as reported for purposes 
of the consolidated return. 
Line 14. Indicator for Nonunitary in Another State – Check the box if the corporation is excluded from a combined 
(“unitary”) return in another state because it is not considered engaged in a unitary business in that state and include 
a statement to identify the state for which the corporation is excluded from the combined return and explain why that 
state does not consider the corporation to be part of the combined group’s unitary business. 
Note: Answer "No" if the group made the controlled group election or if the corporation is a nonmember corporation 
filing Form N with the combined return. 
Line 15. Multiple Return Indicator – If the combined group member was included in another Wisconsin return for 
any part of the period indicated on line 2 (other than a previously filed combined return for the same combined group), 
check the "Yes" box. If that other return was for another combined group, enter the FEIN of that group’s designated 
agent on an attached statement.  
Line 16. Insurance Company Indicator –  Check the "Yes" box if the combined group member is an insurance 
company.  
Note: If the corporation is an insurance company, Form 6I may be required to file to adjust specific to insurance 
companies. See the Form 6I instructions for details. 
Line 17. Tax Exempt Corporation Indicator – Check the "Yes" box if the combined group member is a tax-exempt 
corporation. 
Line 18. Final Return –Check the "Yes" box if the combined group member ceased to exist or withdrew from Wis-
consin during the year and provide a copy of the plan of liquidation and federal Form 966 if the corporation liquidated. 

IC-506 (R. 12-24)                                       54

- 55 -

Enlarge image

                                2024 Form 6 Instructions for Combined Returns 
 
Line 19. Member Joined Group During Year –        Check the "Yes" box if this is the first year that the corporation is 
part of the combined group.  
Line 20. Member Left Group During Year –        Check the "Yes" box if the corporation left the combined group during 
the year. 
Lines 21 and 22 Short Period 

  NOTE: Be sure to use the correct year's tax return when filing for a short period.  If the tax returns are not yet 
  available, wait until the returns become available and file under extension.  For example, if a taxpayer has a short 
  period from January 1, 2025, through March 31, 2025, the 2025 Form 6 will not be ready by July 15, 2025 (unex-
  tended due date for a March 31 year-end).  Wisconsin law provides for an automatic 7-month extension to file the 
  return, so filing under extension will allow the correct years return to be filed when the 2025 Form 6 is available 
  (typically the middle of September 2025).  Note that an extension does not extend the time to pay a balance due.  
  To avoid interest charges, pay the amount due by the unextended due date.    
Line 21. Short Period – If the period included in this return is less than a full year, check the "Yes" box to indicate 
the short period is due to a change in the corporation’s accounting method. 
Line 22. Short Period: Stock Purchase or Sale – If the period included in this return is less than a full year, check 
the "Yes" box to indicate the short period is due to a stock purchase or sale. 
Line 23. Limited Liability Companies – A single-member LLC that is disregarded for federal income tax purposes 
is also disregarded for Wisconsin franchise or income tax purposes. The income from a disregarded entity  owned 
by a member of the combined group must be included in the combined return as if the member itself earned the 
income. Check the "Yes" box if any member was the sole owner of a  disregarded entity and prepare and submit 
Schedule DE with this return. 
Line 24. Limited Liability Companies – Check the box as the sole owner of an LLC.  
Line 25. Use Tax – A corporation may be liable for use tax. Use tax is the counterpart of sales tax. All tangible 
personal property, certain coins and stamps, certain leased properties affixed to real estate, certain digital goods, 
and selected services, taxable under Wisconsin’s sales tax law, which are stored, used, or consumed in Wisconsin, 
are subject to use tax if the proper sales tax is not paid. Examples of purchases that frequently result in a use tax 
liability include, but are not limited to, the following: 
• Mail order and Internet purchases. Wisconsin use tax is owed when such items as computers, furniture, or office 
  supplies are purchased from a vendor who is not registered to collect Wisconsin tax.  
• Inventory. If inventory is purchased without tax for resale, and then used instead of selling them, use tax is owed.  
• Give-aways. Generally, if items are purchased without tax and then given away in Wisconsin, use tax is owed.  
If a taxpayer holds a seller’s permit, use tax certificate, or consumer’s use tax certificate, use tax is reported on the 
sales and use tax return, Form ST-12. Otherwise, Form UT-5 is completed to report use tax. 
For more information on use tax, visit the department’s web site at revenue.wi.gov/html/sales.html, call (608) 266-
2776, or e-mail DORSalesandUse@wisconsin.gov. 
Line 26. Uncertain Tax Positions - If  Schedule UTP-Uncertain Tax Position Statement was required to be com-
pleted with the federal return, include a copy of the schedule with the Wisconsin tax return. 
Line 27. Reportable Transaction Disclosure Statement – If Form 8886-Reportable Transaction Disclosure State-
ment was required to be completed with the federal return, include a copy of the form with the Wisconsin tax return. 
If a corporation was required to include any form with its federal tax return to disclose a “reportable transaction,” as 
defined under sec. 71.81(1)(c), Wis. Stats. ,it must file a copy of that form with the Department of Revenue within 60 
days of the date it is required to file it for federal income tax purposes, provided that it is otherwise required to file a 
Wisconsin return. This includes federal Form 8886, Reportable Transaction Disclosure Statement. To file these forms 
for Wisconsin purposes, check the "yes" box on Form 6, Part VI, line 27 and submit the form with the Form 6. 

Required  Attachments

Include the following items as attachments to the combined Form 6: 
• A copy of the complete federal return of each member of the group (see Methods of Providing Federal Return,  
  earlier in the instructions for alternative ways to meet this requirement) 

IC-506 (R. 12-24)                                           55

- 56 -

Enlarge image

                               2024 Form 6 Instructions for Combined Returns 
 
• If a federal consolidated return is filed, a copy of federal Form 851, Affiliations Schedule, as submitted to the IRS 
• Wisconsin Schedule DE identifying the solely-owned LLCs of each member of the group 
• Any extension of time to file the return 
Other department-prescribed supplemental schedules as described in these instructions, including any attachments 
or additional schedules required per the instructions. 

Additional Information, Assistance, and Forms

Web Resources 
The Department  of Revenue’s web page, available  at    revenue.wi.gov,  has a  number of resources to  provide 
additional information and assistance, including: 
• Related forms and their instructions  
• Department of Revenue Common Questions  
• General Business Common Questions 
• Publications on specific tax topics 
• The Wisconsin Tax Bulletin  
• A home page specifically for combined reporting topics 
• Links to the Wisconsin Statutes and Administrative Code 
   
Contact Information 
If you cannot find the answer to your question on the department’s web page, contact the department using any of 
the following methods: 
• E-mail your question to DORFranchise@wisconsin.gov      
• Call (608) 266-2772  
• (Telephone help is also available using TTY equipment. Call the Wisconsin Telecommunications Relay System 
  at 711 or, if no answer, (800) 947-3529. These numbers are to be used only when calling with TTY equipment.) 
• Send a fax to (608) 267-0834 
• Write to the Audit Bureau, Wisconsin Department of Revenue, Mail Stop 3-107, PO Box 8906, Madison, WI  
  53708-8906 
• Call or visit any Department of Revenue office 
Obtaining Forms 
If you need forms or publications, you may:  
• Download them from the department’s web site at revenue.wi.gov 
• Call (608) 266-1961 
 
                                        Applicable Laws and Rules 
  This document provides statements or interpretations of the following laws and regulations enacted as of the 
 revised date: Chapter 71 Wis. Stats., and Chapter Tax 2, and Chapter 3, Wis. Adm. Code 

IC-506 (R. 12-24)                                      56

PDF file checksum: 945088260

(Plugin #1/10.13/13.0)