- 1). Acquire from the Internal Revenue Service new copies of the same forms used for your original tax return.
- 2). Fill out the tax return with the revised numbers and changes. Do not destroy the previously-filed original return.
- 3). Request Form 1040X from the IRS. The form is available as a printable PDF online. Use the information from the original tax return and the revised tax return to fill out Form 1040X,
- 4). Mail the new tax return along with the completed Form 1040X to the IRS. Any form of filing besides mailing is not allowed for an amended return. Expect to wait 8 to 12 weeks before the IRS processes the amended return.