- 1). Complete a 1040X form. When filing an amendment for your 1040 tax return you will need to complete a 1040X form, Amended U.S. Individual Income Tax Return. This form can be used to correct all 1040 tax returns, including Form 1040, Form 1040A, Form 1040EZ, Form 1040NR and Form 1040NR-EZ.
- 2). Fill in all changes. There are three columns on the 1040X form that will need to be filled in for your amendment. Column A is for the amount you claimed on your original return, Column B is for the amount of the change and Column C is for the correct amount you are filing for. Enter in all numbers for each section you will be amending and calculate any changes.
- 3). Attach copies of forms. Gather all forms, including W-2s, amendments and receipts backing up the reason for filing an amendment. Make copies of the forms and attach with the 1040X form.
- 4). Review form and sign. Check to make sure your numbers are correct and you have added everything properly. Make sure you have included all proper paperwork and that you have signed the bottom of the amendment form.
- 5). Mail form. Send in your amendment with all proper paperwork to the IRS in one envelope. Mail envelope with some sort of delivery confirmation or as a certified letter. This way you have proof that you sent the amendment to the IRS and when they received it.
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