Use Form 1040-X, Amended U.S. Individual Income Tax Return, to correct a previously filed Form 1040-series return (Forms 1040, 1040-SR, or 1040-NR) or to change amounts previously adjusted by the IRS.

If you realize there was a mistake on your return, you can amend it using Form 1040-X, Amended U.S. Individual Income Tax Return.

Situations in which you may need to file an amended return:

• There is a change to your filing status, income, deductions, credits, or tax liability.
• The IRS made an adjustment(s) to your return and sent you a notice that you disagree with, and you want to change the amount(s) adjusted by the IRS.
• You want to claim a carryback due to a loss or unused credit. In this case, you may be able to use Form 1045, Application for Tentative Refund instead of Form 1040-X, which will generally, result in a quicker refund.

If you’re unsure if you should file an amended return, you can use this tax tool to help you decide.

Generally, if you are filing an amended return to claim a refund or credit, you must file your amended return within three years after the date you filed your original return or within two years after the date you paid the tax, whichever is later. However, there are exceptions to the rule in some situations.

When filing your amended return make sure all documents supporting the changes you are making are attached to the return. Failing to supply documents will generally delay processing your return.

Beginning in February 2023, if you electronically file a Form 1040-X for tax year 2021 or later, you can get your refund by direct deposit into either a checking or savings account. You still have the option to submit a paper version of Form 1040-X and receive a paper check.

If the IRS finds mistakes like a math error or missing schedule before you do, you’ll get an IRS notice (typically notice CP2000). . The notice will tell you about the mistake and what information (if any) you need to submit to the IRS to correct it. You do not need to file Form 1040X if you receive a notice and agree with the IRS proposed changes to your return See Incorrect Tax Return for more information. When the IRS sends you a notice about errors, there are usually other ways to correct errors besides an amended tax return.

If you realize there was a mistake on your return, you may be able to amend it using Form 1040-X, Amended U.S. Individual Income Tax Return.

For example, a change to your filing status, income, deductions, credits, or tax liability means you may need to amend your return.  This could occur if you receive an additional Form W-2 after you have already filed your original return.  Or the IRS may have made an adjustment to your return, and sent you a notice with which you disagree.  If so, you would file an amended return to change the amounts adjusted by the IRS.

You can also amend your return to claim a carryback due to a loss or unused credit.  In this case, you may be able to use Form 1045, Application for Tentative Refund instead of Form 1040-X, which will generally result in a quicker refund. But note that you generally have a longer period in which to file a Form 1040-X than a Form 1045, so look closely at the Instructions to Form 1045 to see whether you can use Form 1045.

Generally, if you are filing an amended return to claim a refund or credit, you must file your amended return within three years after the date you filed your original return or within two years after the date you paid the tax, whichever is later. Note, however, that there are numerous exceptions to the general three-year/two-year rule.