Amending Income Tax Returns

General Information

To amend a return, use form TC-40 and the schedules and instructions from the tax year you are amending. See Previous Years’ Forms & Publications to get these forms, or call 801-297-6700 (1-800-662-4335 ext. 6700 if outside the Salt Lake area) to have the forms mailed to you. Enter your reason for amending (see below) and complete your return with all the correct amounts as if you were filing originally. Attach a copy of your amended federal return, if applicable.

If you received a refund, enter the amount of the refund on line 29 of your amended return. If you made a previous payment(s), enter the amount of your payment(s) on line 37 of your amended return. Contributions on line 28 and my529 (UESP) deposits from TC-40, page 3, Part 5 cannot be changed after the original return is filed.

Reasons for Amending

You must amend your return if:

  • You find an error on your Utah or federal return after it has been filed; or
  • Your federal return is audited or adjusted by the IRS and the audit or adjustment affects your Utah return. You must amend your Utah return within 90 days of the IRS’s final determination. Contact the Tax Commission if you are not sure whether your Utah taxes are affected by an audit or adjustment.

Enter one of the following codes that best matches your reason for amending in the “Amended Return” box at the top of the form TC-40.

Code Reasons for Amending
1 You filed an amended return with the IRS. Attach a copy of your amended federal return, Form 1040X. (If amending for a net operating loss, do not use code 1, use code 4 – see below.)
2 You made an error on your original Utah return. Attach an explanation of the error.
3 Your federal return was changed by an IRS audit or adjustment and it affects your Utah return. Attach a copy of the IRS adjustment.
4 You had a net operating loss. Utah treats net operating losses the same as the federal return. If any part of your amended return is for a net operating loss carryback, use code 4 and complete a Utah return for each year you are amending. Attach a copy of your amended federal return, Form 1040X or 1045. Your documentation must clearly show in which year the loss was incurred.
5 Other. Attach an explanation to your return.

Deadlines for Amending

Amended returns should be filed by the later of:

  • Three years after the original due date of the return, including the extension; 
  • Three years after the original due date of the loss year return, including extension, for a net operating loss carried back to preceding years;
  • Two years after the tax was paid; or
  • Two years after the IRS adjusts or accepts an amendment to your federal income tax return, but only to the extent that the changes to the federal return changed information reported on your Utah return such as FAGI, deductions, and federal tax.

How to Amend a Utah Income Tax Return

  1. Enter the “Reason for Amending” code at the top of form TC-40.
  2. Enter the corrected figures on the return and/or schedules.
  3. Line 28 Voluntary contributions from TC-40, page 3. You may add additional contributions on an amended return but cannot reduce the amount you have previously contributed. If you made previous contributions you must still reflect those contributions on this line and on TC-40, page 3.
  4. Line 29 AMENDED RETURN ONLY – previous refund. Do not include refund interest, if any, that you received with the refund. Enter the refund as calculated on your previous return(s) or as adjusted by the Tax Commission, even if you have not yet received the refund, or the refund is:
    1. being carried forward to next year,
    2. deposited into a UESP account, or
    3. used offset to pay other debts
  5. Line 37 AMENDED RETURN ONLY – previous payments. Enter any payments made with or after the prior return(s). Do not report previous payments already reported elsewhere on the return such as withholdings on line 33 or prepayments on line 34.
  6. Submit the amended return with all schedules, including copies of any schedules that did not change from the original filing.
  7. Do not submit a copy of your original return with your amended return.