IL-1120-ST-V: Payment Voucher for Small Business Corporation Replacement Tax (2025)
Illinois · Illinois DOR · Used for tax years 2025
Form IL-1120-ST-V is an Illinois payment voucher for Small Business Corporation Replacement Tax payments made by mail. It identifies the business, tax year ending, and payment amount and can accompany estimated, extension, pass-through, prepayment, or return payments.
Who files this form
Use Form IL-1120-ST-V to make IL-1120-ST payments by mail, including estimated, extension, pass-through, prepayment, or return payments.
Do not file this voucher if no payment is due or you pay electronically. If the Illinois Department of Revenue has notified you that you must pay electronically, you must use one of its electronic payment options.
What you'll need
To complete the voucher and pay by mail, have:
- 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, payable to “Illinois Department of Revenue.”
How to file
Pay by mail
- Enter your FEIN, name, C/O information if applicable, address, and phone number.
- Enter the month and year your tax year ends and your payment amount in whole dollars.
- Detach the voucher and enclose your check or money order, payable to “Illinois Department of Revenue.”
- Write your FEIN, tax year ending, and “IL-1120-ST-V” on the check or money order.
- Mail the completed voucher and payment to:
Illinois Department of Revenue
P.O. Box 19053
Springfield, IL 62794-9053
If you are also filing your return by mail, you may attach the voucher and payment to the front page of your return. Mail them together to the address shown on your return.
Pay electronically
Visit tax.illinois.gov or scan the QR code on the form. Do not file the voucher if you pay electronically. You must pay electronically if the department has notified you that you are required to do so.
Common mistakes
- Filing the voucher when no payment is due or when paying electronically. The form says not to file it in either case.
- Entering cents in the payment amount. Use whole dollars only.
- Mailing a payment when the department has notified you that electronic payment is required. You must use an electronic payment option in that case.
- Not using the voucher for a non-electronic IL-1120-ST payment. The form says to use it for all such payments, including estimated, extension, pass-through, prepayment, and return payments.
Questions people ask
Do I need to send the voucher if I pay electronically?
No. Do not file the voucher if you pay electronically or if no payment is due.
Can I use this voucher for estimated or extension payments?
Yes. Use it for all non-electronic IL-1120-ST payments, including estimated, extension, pass-through, prepayment, and return payments.
What should I write on my check or money order?
Write your FEIN, tax year ending, and “IL-1120-ST-V.” Make it payable to “Illinois Department of Revenue.”
Can I mail the voucher with my return?
Yes. If you file your return by mail, you may attach the voucher and payment to the return’s front page and mail everything to the address shown on the return.
Where can I make an electronic payment?
Visit tax.illinois.gov or scan the QR code on the form. The form encourages electronic payment to avoid mailing delays, save postage and a trip to the post office, and get immediate payment confirmation.