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Instructions for Form 1040-X›(Rev. December 2025)

Purpose of Form

Instruction 1040-X — Instructions for Form 1040-X, Amended U.S. Individual Income Tax Return · 2026-10-03 edition · updated 2026-10-04 · United States

Use Form 1040-X to do the following.

  • Correct Form 1040, 1040-SR, or 1040-NR.

  • Make certain elections after the prescribed deadline (see Regulations sections 301.9100-1 through -3 for details).

  • Change amounts previously adjusted by the IRS. However, don’t include any interest or penalties on Form 1040-X; they will be adjusted accordingly.

TIP

Use these instructions with both the paper-filed Form 1040-X and the electronically filed Form 1040-X.

Extended time to file a claim for refund or credit. Under certain circumstances, you may have additional time to file an amended return to claim a refund or credit. For details, see Federally declared disasters , State-declared disasters , and Combat zones and contingency operations , later.

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▸Contents — Instruction 1040-X — Instructions for Form 1040-X, Amended U.S. Individual Income Tax Return
Instruction 1040-X — Instructions for Form 1040-X, Amended U.S. Individual Income Tax Return

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