Form IL-941-X Important Information and Instructions 

                                          Important Information

Who must file Form IL-941-X?
You must file Form IL-941-X if 
• you need to correct amounts you reported on previously filed Forms IL-941 or IL-941-X, or 
• you disagree with a change we made on your account or the amount of overpayment that was verified for the reporting 
  period,
• you want to request verification of an overpayment.
    You must always report the exact amount of tax that you actually withheld during the reporting period on your Form IL-941 
or Form IL-941-X.
    If you made an error that required a Form IL-941-X and you made the same reporting error on your return and your 
employee’s Form W-2 or payee’s Form 1099 or W-2G, you must also provide your employee or payee with a Form W-2c or 
corrected Form 1099 or W-2G, and attach copies to your Form IL-941-X.
How can I file or pay electronically?
We encourage you to file your Form IL-941-X and make your payments electronically.   
To file — You may use 
• MyTax Illinois 
• an IDOR-approved tax-prep software program (software you develop or purchase off-the-shelf) to file electronically. 
To pay — You may use
• MyTax Illinois  
• an IDOR-approved tax-prep software program, or
• ACH Credit payment option.
MyTax Illinois is our online account filing and management program that is available to you, free of charge, to file, pay, and 
monitor your Illinois tax accounts. 
NOTE: Any Forms IL-941 and IL-941-X filers with more than 32,767 employees cannot use MyTax Illinois and must use 
third-party software to file their return.

When shouldn’t I file Form IL-941-X?
• Do not file Form IL-941-X if you reported the amount you actually withheld, even if you withheld the wrong amount.
• If you discover an error in withholding before the end of the year, you should correct the error by adjusting the amount you 
  withhold on the following quarter.
• If you cannot correct the error before the end of the year, you must make sure that your withholding tax return and each 
  employee’s or payee’s Form W-2, W-2G, W-2c, or 1099 report the actual amount withheld. The employee or payee will 
  account for the exact amount of tax you withheld on his or her income tax return.
• To correct a payment that was applied to an incorrect period, you must send a written request to have the payment moved.  
  In your written request, please include your account number; the amount and date of the payment; the period to which the 
  payment was applied; the period to which the payment needs to be applied; and the reason for your request to move the 
  payment. Also include a complete list of payment amounts and dates for both periods.  Send the request to the address 
  listed in the “Where do I get help?” section.
• You realize, after you issued the employee’s W-2 for the calendar year, you withheld too much from the employee in 
  a prior quarter, however you reported the exact amount you withheld on the quarter’s Form IL-941 and Form W-2 for 
  that employee. Even though the amount you withheld was not correct, do not refund the over-withheld amount to the 
  employee, do not file an amended return, and do not file an amended W-2 changing the withholding amount.  The amount 
  you reported on your Form IL-941 and your employee’s Form W-2 is correct in that the amount was exactly what you 
  withheld. The over-withheld amount will be credited to the taxpayer when he or she files his or her individual income tax 
  return. Note: If the wages reported were incorrect, you will need to issue a corrected W-2 to report the correct amount of 
  Illinois wages, but the Illinois withholding should not change.
For additional information and details, see the instructions for Form IL-941.  

When is Form IL-941-X due?
You should report increases in your tax due immediately to minimize penalties and interest. If your change decreases your tax 
due, file Form IL-941-X no later than 
• three years after the 15th day of the 4th month following the close of the calendar year in which the tax was withheld, or 
• one year after the date the tax was paid, whichever is later. Make sure to allow time for processing.
You may be assessed penalties and interest if your Form IL-941-X is filed after the due date of your original return. If so, we will 
send you a notice.  

IL-941-X Instructions (R-12/21)                                                                        Page 1 of 5 

          Form IL-941-X Important Information and Instructions 
What are the penalties and interest?
For information about penalties and interest, see Publication 103, Penalties and Interest for Illinois Taxes.

Which steps must I complete?
You must complete every step to report changes previously reported on your Forms IL-941 or IL-941-X. If we agree that you 
have a valid overpayment, it will first be applied to any outstanding withholding income tax liabilities.  Then it may be refunded 
depending on fund availability.

What do I need to attach to my Form IL-941-X as support?
You must attach your completed Form Schedule P-X, Amended Illinois Withholding Schedule, and if required, a Schedule WC, 
Withholding Income Tax Credits. In addition, if you are filing this IL-941-X for a previous calendar year, you must electronically 
submit all annual withholding forms that report Illinois withholding, including Forms W-2, W-2G, W-2c, and 1099 to IDOR. 
For more information on reporting requirements, please see Publication 110, Forms W-2, W-2c, W-2G, and 1099 Filing and 
Storage Requirements for Employers and Payers, including 1099-K Electronic Filing Requirements.
    Go to our website at tax.illinois.gov for more information on our W-2 electronic transmittal options, including MyTax 
Illinois.

Where do I get help?
•  Visit our website at tax.illinois.gov
•   Call us at 1 800 732-8866 or 217 782-3336
•  Call our TDD (telecommunications device for the deaf) at 1 800 544-5304
•  Write to :
   ILLINOIS DEPARTMENT OF REVENUE
   PO BOX 19001
   SPRINGFIELD IL 62794-9001
•  For more information about Illinois withholding income tax, seePublication 130,Publication 131, and Form IL-941 
   Instructions.

                                Step-by-Step Instructions

Step 1:  Provide your information
Enter your information and check any box that is applicable. 

Reporting Period — Check the same box that was checked on the Forms IL-941 or IL-941-X you are amending. 
   
Step 2:  Tell us about your business

Item A1 — Enter the total number of W-2 forms reporting Illinois withholding you were required to issue for the entire year. Only 
complete this line when you file your 4th quarter or final return.
Item A2 — Enter the total number of 1099 forms reporting Illinois withholding you were required to issue for the entire year. 
Only complete this line when you file your 4th quarter or final return.
Item B — Complete this line only if you have permanently stopped withholding and this is your final return. 

Steps 3 through 5: 
Follow the instructions on the form and enter the corrected amounts for each line.  

Step 3:  Tell us about the amount subject to withholding
Line 1 — Enter the total of all amounts subject to Illinois withholding income tax (either required or by voluntary agreement) 
including payroll, compensation, gambling winnings (such as Illinois Lottery winnings and sports wagering winnings), amounts 
paid to purchase the rights to Illinois Lottery winnings, or any other wage or non-wage income. Do not leave blank - if you had 
no amount subject to Illinois withholding, enter zero.
Step 4:  Tell us about the amount withheld and previous overpayments
Line 2 — Enter the exact amount of Illinois Income Tax you withheld from your employees’ or others’ income on the date you 
paid the compensation. This step is separated by month and lists every day in each month. Enter the amount of Illinois income 
tax you withheld from your employees or payees on the exact day you paid the amount from which you withheld tax.
IL-941-X Instructions (R-12/21)                                                                                     Page 2 of 5 

            Form IL-941-X Important Information and Instructions

1.  Enter the amount of Illinois Income Tax you withheld from your employees’ or payees’ income on the exact day you 
  withheld it. Do not write this amount on the day you made your deposit — it must be the day you made your payroll or 
  compensation payments.  For example, If your payroll is paid on January 15 and January 30 and you withheld a total of 
  $300 each payroll, you will enter $300 on the 15th and $300 on the 30th in the “First month of quarter” section.
    15              $300.00     
       30           $300.00     

2.  For each month add the daily amounts to determine the total tax withheld for the month and enter the total in the space 
  provided. For this example, you would enter $600 on Line 2a.

                                                                                                       $600.00

3.  For each quarter, add the amounts from Lines 2b, 2c, and 2d, and enter the total on the line provided and on Form 
  IL-941-X, Line 2.

                                                                                                       $1,800.00

IMPORTANT:  Enter the total of all amounts of Illinois Income Tax actually withheld (either required or by voluntary agreement) 
this reporting period, even if you are able to use a credit to pay your withholding liability.  This includes employee withholding 
and any withholding that was made on other Illinois income.Do not estimate this amount. Do not leave the total line for 
Line 2 blank- if you did not withhold during this period, enter zero. 

Line 3 — Enter the total amount of credits resulting from this period.
This amount should include the following:
•       Any credits that you were previously allowed to use to offset a liability on another period
•       Any refund that you received
•       Any overpayment amount used to pay the penalty and interest on the period

Note: Do not include the Minimum Wage, EDGE, or ILSBJC credits that were not used towards your tax liability on this period.

Line 4 — Follow the instructions on the form. 

Step 5:  Tell us about your payments and credits
Line 5 - Enter the amount from Schedule WC, Line 7. If you are claiming a credit, you must attach Illinois Schedule WC and 
any other required support listed on Schedule WC. For more information, see Illinois Schedule WC Instructions, and Schedule 
WC-I, Withholding Income Tax Credits Information and Worksheets. 

Note: The Department applies credit and payments in a specific order. The withholding credits (Line 5) are applied first, 
and then the payments (Line 6).

Line 6 — Enter the total amount of withholding payments you have made during this period. This includes all IL-501 payments 
(electronic and paper coupons) and any payments submitted with Form IL-941 or Form IL-941-X previously filed for this period.  
Do not include payments you are submitting with this Form IL-941-X. Do not leave blank.

Line 7 — Follow the instructions on the form.

Step 6:  Figure your balance
Line 8 — Follow the instructions on the form.  This is your balance due.
Line 9 — Follow the instructions on the form. NOTE: Any approved overpayment will be offset to any outstanding tax liabilities 
and then refunded. Verified credits are not available to be carried forward to future tax liabilities. 

IL-941-X Instructions (R-12/21)                                                                                   Page 3 of 5 

         Form IL-941-X Important Information and Instructions

Step 7:  Sign here
You, or a person authorized by you through a Power of Attorney form, must sign and date the first signature line of your return. 
If you do not sign your return, it will be considered not filed and you may be subject to a nonfiler penalty. The paid preparer 
line must be completed by a person whom you paid to complete the return and who is not your employee. Enter the paid 
preparer’s IRS Preparer Tax Identification Number (PTIN) in the space provided. If you want to allow a person, other than 
yourself, to discuss this return with us, check the box and print the designee’s name and phone number. This authorization will 
allow your designee to answer any questions that arise during the processing of your return, call us with questions about your 
return, and receive or respond to notices we send. The authorization will automatically end no later than one year from the due 
date of this return. You may revoke the authorization at any time by calling or writing us.

                                Schedule P-X Instructions
Schedule P-X paper form instructions: 

Step 1: Enter all payee’s/employee’s names and Social Security numbers in the same order as reported on your original 
IL-941, Schedule P, for the reporting period. NOTE: If you are correcting an employee’s Social Security number, you will 
make two separate entries. You will first enter the employee’s incorrect Social Security number, showing zero wages and 
zero withholding. You will make a second entry with the corrected Social Security number, along with the correct wages and 
withholding amounts. 

Step 2: Enter the corrected income and withholding amounts for each payee employee listed on your original IL-941, Schedule 
P for the reporting period. List any new payee/employee information last. Check the box in the first column if the income and 
withholding information for the payee or employee has changed.
NOTE: If you have zero wages and withholding for the reporting period, complete Schedule P-X by entering your business 
name, FEIN, and zeroes in both the income and withholding columns. If you are amending your return to show zero income or 
withholding, you may receive a request for additional information. 

Schedule P-X CSV file format and instructions for filing at MyTax Illinois

The CSV file format is used for importing Schedule P-X Illinois Withholding Payroll Schedule directly to a withholding account.  

The import feature is recommended for users who have a spreadsheet software program that can create the CSV format. Us-
ing a spreadsheet program (i.e., Excel), four columns are required to create a CSV file that is recognized and accepted by 
MyTax Illinois.

Step 1: Create your spreadsheet
The spreadsheet should be set up as follows:

               Field Name       Maximum Length           Data Entry                         Description
Column 1 Employee Name          30 characters            Alpha/Numeric The full name of the employee. Do not enter periods 
                                                                       after initials. For example, John R. Doe should be 
                                                                       entered as ‘John R Doe’.
Column 2       SSN              9 characters             Numeric       The Social Security number of the employee. No 
                                                                       hyphens are necessary. For example, 000-00-000 
                                                                       should be entered as 000000000.
Column 3       Income           13 characters            Numeric       The employee’s income for the quarter. Enter as 
                                                                       unformatted dollars and cents. For example, 
                                                                       $1,234.56 should be entered as ‘1234.56’ and 
                                                                       $1,234.00 should be entered as ‘1234’.  
Column 4       Withholding      13 characters            Numeric       The amount withheld on behalf of the employee 
                                                                       for the quarter. Enter as unformatted dollars and 
                                                                       cents. For example, $1,234.56 should be entered as 
                                                                       ‘1234.56’ and $1,234.00 should be entered as 
                                                                       ‘1234’. 

IL-941-X Instructions (R-12/21)                                                                                Page 4 of 5 

                                Schedule P-X Instructions 

You cannot import more than 32,767 rows. Any filers with more than 32,767 employees must use Federal/State Employment 
Taxes (FSET) or third-party software to file the return. For additional information, see the FSET program. 

CSV Spreadsheet Example (i.e. Excel)
John R Doe    000000000         1234.56 100

Text File Example (i.e. Notepad)
John R Doe,000000000,1234.56,100
When all employee data has been entered, the file is then saved.  You will name the spreadsheet file accordingly and just below 
the File Name is the ‘Save As’ box. In the most current version of Excel, you will click the scroll down arrow and select the ‘CSV 
– (Comma delimited)’ option. For older versions of Excel, you will select the ‘CSV – Comma Separated Value’ option. This will
configure the spreadsheet into the format that is accepted by MyTax Illinois.
Step 2: Upload your spreadsheet to MyTax Illinois
Once the spreadsheet is complete, you will log on to MyTax Illinois, using your username and password. Click ‘Log In’ and follow 
the steps below:
1. Click on ‘File a Return” in the Withholding account box.
2. Navigate to the appropriate filing period to file a return (Forms IL-941 and IL-941-X).
3. When completing the return, select the ‘Import payroll data from a saved file’ option.
4. On the following page, click the ‘Import Payroll Data’ option.
5. Select the CSV file saved on your computer by clicking ‘Choose File’.
6. Click on the file name of the file you want to import.
7. Click ‘Ok’.
8. The employee information will display and if everything is correct, you will select ‘Use Imported Payroll Data’.
9. After the file has imported, you may update or add individual rows to your Schedule P.
10. Click ‘Next’ to continue and complete your return.

For more information, see the 2022 Form IL-941 Instructions.

                                Mail your completed Form IL-941-X and support to:

                                        ILLINOIS DEPARTMENT OF REVENUE 
                                        PO BOX 19052
                                        SPRINGFIELD IL  62794-9052

                                Printed by authority of the state of Illinois - web only, one copy.
IL-941-X Instructions (R-12/21)                                                                                    Page 5 of 5