Form 1040-X: Amended U.S. Individual Income Tax Return

You file Form 1040-X when you find an error after filing a Form 1040, 1040-SR, or 1040-NR. You also use it to change amounts the IRS already adjusted, to claim a carryback from a loss or unused credit, and to make certain elections after the prescribed deadline. File a separate Form 1040-X for each tax year you are fixing. You can amend the same year more than once, as long as each Form 1040-X is filed on time.

Some fixes belong on a different form. If you only want back penalties or interest you already paid, file Form 843 instead. If you want your share of a joint overpayment that was offset against your spouse's past-due obligation, file Form 8379. Changing your federal return may mean you need to change your state return too.

• Use it to correct Form 1040, 1040-SR, or 1040-NR
• Use it if you filed Form 1040 when you should have filed Form 1040-NR, or the reverse
• Do not file another original return for the same year after the due date has passed

File it only after your original return is in. For a credit or refund, you generally have 3 years (including extensions) after the date you filed the original return, or 2 years after the date you paid the tax, whichever is later. If you filed early, say March 1 for a calendar year return, your return counts as filed on the due date, generally April 15. If you had an extension until October 15 but the IRS received your return on July 1, it counts as filed July 1.

A few claims run longer. A claim based on a bad debt or worthless security must generally be filed within 7 years after the due date of the return for the year the debt or security became worthless. A claim for a foreign tax credit, or a change from a deduction to a credit for foreign income taxes, must generally be filed within 10 years from the due date of the return for the year the taxes were paid or accrued.

• Federally declared and qualified State-declared disasters can give you more time
• Combat zone or contingency operation service can extend the deadline automatically
• The deadline for the section 174A election on domestic research costs is July 6, 2026

Enter the calendar year or fiscal year you are amending at the top, then your name, current address, and SSN or ITIN. Check one filing status box even if your status is not changing. Lines 1 through 23 use three columns. Column A is the original amount you reported or the amount as previously adjusted. Column B is the net increase or decrease. Column C is the correct amount, which you get by adding the increase or subtracting the decrease from column A. Show losses and decreases in parentheses.

Part II is required on every Form 1040-X. Write out why you are filing, such as receiving another Form W-2 or forgetting the child tax credit. Complete Part I if anything about your dependents changes. Sign and date the form, and have your spouse sign too on a joint amended return. On paper, your signature must be handwritten. Attach every form and schedule that supports your changes, or the return will be sent back to you.

• Changing only filing status, income, or deductions means completing lines 1 through 23
• Changing only payments and refundable credits means completing lines 11 through 23
• Part III lets e-filers ask for direct deposit of the line 22 refund for tax year 2021 or later
• A refund on a paper-filed amended return cannot go straight to your bank account

Paper filers now have to attach a completed and updated Form 1040, 1040-SR, or 1040-NR showing the changes, placed behind the finished Form 1040-X. Line 4a is now where the qualified business income deduction goes. New line 4b covers the deductions for tips, overtime, car loan interest, and seniors from Schedule 1-A (Form 1040), which was introduced in 2025. Attach your Schedule 1-A if you claim any of those.

Form 8379 can be filed electronically by attaching it to an electronically filed Form 1040-X, even if you are not amending anything else. Do not attach Form 4547 to Form 1040-X. Two timing changes also arrived: qualified State-declared disasters can give you more time to claim a credit or refund for declarations made after July 24, 2025, and the lookback period for refund claims has been extended in certain situations.

You can file Form 1040-X electronically with tax filing software to amend Forms 1040, 1040-SR, and 1040-NR. If you file on paper in response to an IRS notice, mail it to the address shown in that notice. If you are filing it with a Form 1040-NR, or you live in a foreign country or U.S. territory, use an APO or FPO address, file Form 2555 or 4563, or are a dual-status alien, mail it to Austin, TX 73301-0215.

Otherwise the address depends on where you live. Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, Oklahoma, and Texas go to Austin, TX 73301-0052. A group of mostly western and midwestern states goes to Ogden, UT 84201-0052. A group of mostly eastern states goes to Kansas City, MO 64999-0052. All three are Department of the Treasury, Internal Revenue Service. Allow 8 to 12 weeks for processing, and up to 16 weeks in some cases. It can take up to 3 weeks from the day you mail it before it shows up in the IRS system.

• Track it with Where's My Amended Return using your TIN, date of birth, and ZIP code
• If you owe and do not pay electronically, enclose your check or money order, do not attach it
• Private delivery services cannot deliver to an IRS P.O. box