IL-1120-ST-X-V: Payment Voucher for Amended Small Business Corporation Replacement Tax (2025)
Illinois · Illinois DOR · Used for tax years 2025
Form IL-1120-ST-X-V is an Illinois payment voucher for amended Small Business Corporation Replacement Tax. It records your federal employer identification number (FEIN), contact information, tax year ending, and payment amount in whole dollars.
Who files this form
Use Form IL-1120-ST-X-V when sending a check or money order with your amended Illinois Small Business Corporation Replacement Tax return.
Do not file this voucher if no payment is due or if you pay electronically.
What you'll need
Have these items and details ready:
- Your amended return.
- Your federal employer identification number (FEIN).
- Your name, C/O information if applicable, mailing address, and phone number.
- The month and year your tax year ends.
- The amount you are paying, in whole dollars.
- A check or money order for that amount.
How to file
- Enter your FEIN, name, C/O information if applicable, address, and phone number.
- Enter the month and year your tax year ends.
- Enter your payment amount in whole dollars only.
- Make your check or money order payable to “Illinois Department of Revenue.” Write your FEIN, tax year ending, and “IL-1120-ST-X-V” on it.
- Detach the completed voucher. Attach the voucher and payment to your amended return and mail them to:
Illinois Department of Revenue
P.O. Box 19016
Springfield, IL 62794-9016
If you pay electronically, do not file this voucher.
Common mistakes
- Filing the voucher when no payment is due or when paying electronically. The form specifically says not to file it in either case.
- Entering cents in the payment amount. Use whole dollars only.
- Leaving identifying information off your check or money order. Include your FEIN, tax year ending, and “IL-1120-ST-X-V.”
- Making the payment payable to someone other than “Illinois Department of Revenue.”
Questions people ask
Do I need to file this voucher if I pay electronically?
No. The form says not to file the voucher if you pay electronically or if no payment is due.
What should I write on my check or money order?
Write your FEIN, tax year ending, and “IL-1120-ST-X-V.” Make it payable to “Illinois Department of Revenue.”
Should I include cents in the payment amount?
No. Enter the payment amount in whole dollars only.
Do I send the voucher with my amended return?
Yes. Attach the completed voucher and payment to your amended return, then mail them to the address printed on the voucher.