What Form Is Used to Re-Do a Previous Year's Tax Return?

Changes to previous-year returns must be reported within three years.

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If you need to revise a previous tax year's tax return for any reason, the Internal Revenue Service requires that you file an amended return. You must also amend your return if your filing status or number of dependents changes. The form you file to report an amendment is Form 1040X. It includes line items on the front with space on the back of the form to explain any changes. You also have to file, along with the 1040X, any schedules to which you make changes.

Step 1

Check the date. You can file an amended return up to three years after the filing date of the original return.

Step 2

Get out the previous year's return for reference. You can use data from the original form, making changes only where figures are being updated.

Step 3

Grab the new or additional tax data. If you have received more W-2s or Forms 1099, have those in hand before you start the amended return.

Step 4

Download Form 1040X from the IRS website. You can also ask for the form by phone or by mail.

Step 5

Add the new data to any required schedules. For example, new interest income (1099-INT) is reported on Schedule B. New self-emplotyment income should be entered on Schedule C. Redo any calculations that derive from the changes.

Step 6

Fill out the front of Form 1040X with the new income and deduction totals. You would also add changes in filing status to the front of the form. Use Part III on the reverse of Form 1040X to explain the changes. For example, you might write in Part III that your Form 1099-MISC arrived after you had already filed your return.

Step 7

Sign, date and mail the form to the address specified in the instructions.