What Is a Tax Amendment and When Should You File One?

A tax amendment serves as a formal correction to a federal income tax return that has already been filed. Its primary function is to rectify errors or omissions made on the original submission. This process allows taxpayers to adjust their previously reported tax liability, which might result in either receiving an additional refund or owing more tax to the government.

Reasons to Amend

Common situations require filing an amended tax return to correct inaccuracies. This includes incorrect income reporting, such as receiving a corrected W-2 or 1099 form after filing, or miscalculating self-employment income. These discrepancies directly impact the calculation of adjusted gross income and subsequent tax obligations.

Another common scenario involves errors related to deductions or credits. Taxpayers might realize they forgot to claim an eligible deduction, such as student loan interest or contributions to a retirement account, which could reduce their taxable income. Miscalculations or incorrect claims for tax credits, like the Child Tax Credit or education credits, also require an amendment. Changes in filing status, such as realizing one should have filed as Head of Household instead of Single, or errors in reporting dependents, also warrant an amended return. These situations involve factual inaccuracies or omissions on the original return that directly affect the final tax outcome.

Steps for Preparing an Amendment

Preparing a tax amendment begins with Form 1040-X, Amended U.S. Individual Income Tax Return. This form is used by individuals to correct previously filed Forms 1040, 1040-SR, or 1040-NR. Taxpayers can obtain Form 1040-X directly from the Internal Revenue Service (IRS) website.

Before starting, gather essential information, including a copy of the original tax return for the year being amended and any new or corrected tax forms. This also includes supporting documents like corrected W-2s, 1099s, or receipts for new deductions. Form 1040-X requires entering the original figures from the filed return in Column A, the net changes in Column B, and the corrected amounts in Column C.

The “Explanation of Changes” section of Form 1040-X requires a clear and concise explanation for each change, such as “Amending return to include previously unreported freelance income.” While supporting documents like corrected W-2s or Schedule A should be referenced, their physical attachment occurs during the submission phase.

Submitting Your Amendment

Once Form 1040-X is completed, submit it to the IRS. Individual taxpayers can now e-file amended returns through tax software for the current tax year and the two prior tax periods if the original return was also e-filed. If the original return was paper-filed, or for tax years beyond the electronic filing window, the amended return must be mailed.

The mailing address for Form 1040-X varies by state of residence or where the original return was filed. Consult the official IRS instructions for Form 1040-X for the correct mailing address. Enclose only Form 1040-X and any necessary supporting documents directly related to the changes, such as corrected W-2s, 1099s, or revised schedules. Do not attach a copy of the original Form 1040, as Form 1040-X reflects the changes. If a payment is due, enclose it with the return but do not attach it to the form.

What Happens After Filing

After submitting your amended tax return, the IRS begins processing. Form 1040-X processing time is longer than for an original return, often taking 8 to 16 weeks, or more if further review is needed. Wait at least three weeks after submission before checking its status.

Taxpayers can track the status of their amended return using the “Where’s My Amended Return?” online tool on the IRS website. This tool requires the taxpayer’s Social Security number, date of birth, and ZIP code to provide updates. The “Where’s My Refund?” tool does not provide status updates for amended return refunds; only the “Where’s My Amended Return?” tool should be used.

If the amendment results in a refund, it will be issued via direct deposit or a paper check. If additional tax is owed, payment instructions will be provided, and interest and potential penalties may apply if the original payment was insufficient. The IRS may also contact the taxpayer for additional information or clarification during the review process.