Amending Income Tax Returns

General Information

To amend a previously-filed return, use the tax forms and instructions for the year you are amending. Get prior year forms and instructions at

Amend your return if you find an error on your Utah or federal return, or if your federal return is audited or adjusted by the IRS in a way that affects your Utah return. You must amend your Utah return within 90 days of the IRS’s final determination.

See Deadlines to Claim a Refund or Credit for deadline information.

How to Amend a Utah Income Tax Return

  1. On the top of TC-40, page 1, on the “Amended Return” line, enter the code number from the list below that best describes your Reason for Amending.
  2. Enter the corrected figures on the return and/or schedules.
  3. Enter all other amounts as shown on your original return. If you received a refund on your original return, enter the amount of the previous refund on the appropriate line of the amended return. If you paid with the original return or made subsequent tax payments before filing the amended return, enter the total previous payments on the appropriate lines of your amended return. Contributions and my529 deposits cannot be changed after the original return is filed.
  4. Submit the amended return with all schedules, including copies of those schedules that did not change from the original filing.
  5. Do not submit a copy of your original return with your amended return.

Reasons for Amending

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 federal 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 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 from 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 the year you experienced the loss.
5 Other. Attach an explanation to your return.

Instructions for TC-40, Line 29 – Previous Refund

This line is only for an amended return. Enter the total of all refunds, credits, and offsets of state income tax received for the tax year being amended. Do not include refund interest.

Instructions for TC-40, Line 37 – Previous Payment

Use this line only for an amended return. Enter the total tax paid with the original return plus any later tax payments for the tax year being amended. Do not include on this line any penalty, interest or fees paid on the previous return.