How to Correct Last Year's Tax Return
- 1). Print a copy of form 1040X, the form used to amend federal individual income tax returns. You can fill out the 1040X online and print it already filled out or you can print a blank form and fill it out by hand. The only way to file an amended return is through the mail. Electronic amendments are not available as of 2011.
- 2). Gather your tax information used on last year's return, including any additional information you've come across that was not included on your tax return, as well as a copy of last year's return.
- 3). Use last year's return and your tax information to fill out your 1040X. Explain each of the changes you are making to the amended return in detail, in the space provided. Attach an additional sheet of paper if you run out of space to explain your changes. Amendments allowed on income tax returns include mistakes in reporting dependents, deductions, income, credits and/or filing status.
- 4). Sign the amended return and mail it to the address in the instruction manual specified for residents of your state. Amended returns take longer to process than other returns, but you will hear from the IRS if it has questions about your amended return.
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