Amended Return (Form 1040X)

IRS Definition

If you need to make a change or adjustment on a return already filed, you can file an amended return. Use Form 1040X, Amended U.S. Individual Income Tax Return, and follow the instructions. Form 1040X cannot be filed electronically. 

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If you discover a mistake after you file your tax return, you may need to change (amend) your return. To amend your return, use IRS Form 1040X, Amended U.S. Individual Income Tax Return. If you receive a notice from the IRS about an error, you usually do not have to file an amended return unless the notice specifically asks you to.

If you are filing an amended return to claim a refund of tax you already paid, you must file the Form 1040X within three years of the date you filed your original return or within two years of the date you paid the tax, whichever is later.

Amended returns must be filed by paper.

Learn more about amended returns and amended return denials.