Info courtesy of IRS.gov

Don’t worry if you made a mistake on your tax return or forgot to claim a tax credit or deduction. You can fix it by filing an amended return.

1. When to amend.  You should amend your tax return if you need to correct your filing status, the number of dependents you claimed, or your total income. You should also amend your return to claim tax deductions or tax credits that you did not claim when you filed your original return.

2. When NOT to amend.  In some cases, you don’t need to amend your tax return. The IRS usually corrects math errors when processing your original return. If you didn’t include a required form or schedule, the IRS will send you a request for the missing item.

3. Form to use.  Use Form 1040X (for individual income tax return) to amend a federal income tax return that you previously filed. Make sure you check the box at the top of the form that shows the year you are amending.  Mail it to the IRS.

4. More than one year.  If you file an amended return for more than one year, use a separate Form 1040X for each tax year and mail them in separate envelopes to the IRS.

5. Form 1040X.  Form 1040X has three columns. Column A shows amounts from the original return. Column B shows the net increase or decrease for the amounts you are changing. Column C shows the corrected amounts. You should explain what you are changing and the reasons why on the back of the form.

6. Other forms or schedules.  If your changes involve other tax forms or schedules, make sure you attach them to Form 1040X when you file the form.

7. Amending to claim an additional refund.  If you are waiting for a refund from your original tax return, don’t file your amended return until after you receive the refund. You may cash the refund check from your original return.

8. Amending to pay additional tax.  If you’re filing an amended tax return because you owe more tax, you should file Form 1040X and pay the tax as soon as possible. This will limit any interest and penalty charges.

9. When to file.  To claim a refund, you generally must file Form 1040X within three years from the date you filed your original tax return.