If you need to amend your tax return, use Form 1040X, Amended U.S. Individual Income Tax Return.
Use Form 1040X to correct previously filed Forms 1040, 1040A or 1040EZ. The 1040X can also be used to correct a return filed electronically. However, you can only paper file an amended return.
You should file an amended return if you discover any of the following items were reported incorrectly: filing status, dependents, total income, deductions or credits.
Generally, you do not need to file an amended return for math errors. The IRS will automatically make the correction.
You usually do not need to file an amended return because you forgot to include tax forms such as W-2s or schedules. The IRS normally will send a request asking for those documents.
Be sure to enter the year of the return you are amending at the top of Form 1040X. Generally, you must file Form 1040X within three years from the date you filed your original return or within two years from the date you paid the tax, whichever is later.
If you are amending more than one tax return, prepare a 1040X for each return and mail them in separate envelopes to the IRS campus for the area in which you live. The 1040X instructions list the addresses for the campuses.
If the changes involve another schedule or form, you must attach it to the 1040X.
If you are filing to claim an additional refund, wait until you have received your original refund before filing Form 1040X. You may cash that check while waiting for any additional refund.
If you owe additional tax for 2009, you should file Form 1040X and pay the tax as soon as possible to limit interest and penalty charges. Interest is charged on any tax not paid by the due date of the original return, without regard to extensions.