IL-990-T: Exempt Organization Income and Replacement Tax Return (2025)

When it's due

For the 2025 Form IL-990-T, the return is due on or before the 15th day of the 5th month following the close of the tax year. For employee trusts, it is due on or before the 15th day of the 4th month following the close of the tax year.

This version is for tax years ending on or after December 31, 2025, and before December 31, 2026. If your return is not for calendar year 2025, enter your fiscal tax year beginning and ending dates.

What you'll need

• Federal Form 990-T: Attach a copy to support the unrelated business taxable income or loss on Line 1.
• Organization information: Have your legal business name, mailing address, FEIN, nature of your unrelated trade or business, and NAICS code, if applicable.
• Credit and recapture forms, when applicable: Attach Schedule 4255 for investment credit recapture, Form IL-477 for investment credits, and Schedule 1299-D for income tax credits.
• Payment and withholding records: Have records of prior overpayment credits and payments. Attach Schedules K-1-P or K-1-T for reported pass-through withholding or pass-through entity tax credits, and Forms W-2G for Illinois income tax withholding.
• Special attachments: Attach a detailed statement if an overpayment carryforward is going to a different FEIN. Include Form IL-990-T-V if mailing a payment.
• Direct deposit information: Have your routing number, account number, and checking or savings account designation if requesting direct deposit.

How to file

Complete the organization information, income and tax calculations, and refund or balance due sections. Have an authorized officer sign and date the return and provide their title and phone number.

Mail without an enclosed payment:

Illinois Department of Revenue

P.O. Box 19009

Springfield, IL 62794-9009

Mail with an enclosed payment:

Illinois Department of Revenue

P.O. Box 19053

Springfield, IL 62794-9053

If you owe tax on Line 35, the form directs you to make an electronic payment at Tax.Illinois.gov. If you must mail payment, complete Form IL-990-T-V. Make your check or money order payable to “Illinois Department of Revenue” and write your FEIN, tax year ending, and “IL-990-T-V” on it. Attach the voucher and payment to the front of the return.

The form provides electronic payment directions, but does not provide directions for e-filing the return.

Common mistakes

• Completing Step 3 when it must be blank: If Line 3 income is derived only inside Illinois, or you are an Illinois resident trust, check Box A, carry Line 3 to Line 12, and leave Lines 4 through 11 blank.
• Leaving required Step 3 lines blank: If any portion of Line 3 is derived outside Illinois, check Box B and complete all of Step 3. Do not leave Lines 6 through 8 blank.
• Entering negative sales: Lines 6 and 7 cannot be negative.
• Forgetting the payment amount: Enter the amount paid with the return at the top of Page 1.
• Omitting required information: The form warns that failure to provide required information could result in a penalty.

Questions people ask

What replacement tax rates are printed on the form?

For Line 13, corporations multiply Line 12 by 2.5% (.025), and trusts multiply it by 1.5% (.015).

Can I receive my refund by direct deposit?

Yes. Complete Line 34 with your routing number, account number, and checking or savings account designation.

Can I apply an overpayment forward instead of receiving it all as a refund?

Line 32 lets you enter an amount to credit forward. Line 33 subtracts that amount from your overpayment to calculate the refund. If the carryforward is going to a different FEIN, check the box and attach a detailed statement.

What should I do if this is my first or final return?

Check the applicable box or boxes in Step 1, Item C. For a final return, also enter the date of termination.

Official sources

• https://tax.illinois.gov/content/dam/soi/en/web/tax/forms/incometax/documents/currentyear/business/taxexempt/il-990-t.pdf