How to File an Amended Tax Return

If you discover a mistake or missed deduction after filing, you generally have the option to file an amended return. Here's a general overview of how that process typically works — always confirm the specifics with a licensed tax professional or the IRS.

When an amended return generally makes sense

Common reasons include a missed deduction or credit, an incorrect filing status, unreported income you later discovered, or a correction to your number of dependents.

The general form used

Form 1040-X is the form used to amend a previously filed federal individual income tax return. It generally asks you to show the original figures, the corrected figures, and an explanation of the changes.

General timing

There is generally a window of time within which an amended return can be filed to claim an additional refund; specific deadlines can vary based on your situation, so confirm your exact deadline with a tax professional or the IRS rather than relying on a general rule.

What to gather first

Before amending, it generally helps to have your original return, any new or corrected documents (like a corrected W-2 or a 1099 you forgot), and a clear explanation of what changed.

Tracking your amended return

The IRS generally provides a way to check the status of an amended return separately from an original return's refund status, and amended returns typically take longer to process.

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