Every year by April 15, your tax returns are due unless you file for an extension. During the year, you are supposed to keep all the records needed to complete your tax returns correctly. However, in some cases, you may have forgotten to include something or claimed something you later found out was not allowable. In the event your tax refund was incorrect, you need to make the necessary corrections as soon as possible.
Tax Return Errors
If you notice you made a math error when you calculated your federal tax return, you should not file an amended return because the government generally catches these errors. You should file an amended return if your refund was incorrect due to an error in reporting credits, deductions, expenses or income. However, the Internal Revenue Service says that if you expect a refund, wait until you receive the refund before amending the return.
Federal Amended Return
Amending an incorrect federal tax refund is done by using Form 1040X, whether you originally submitted forms 1040NR-EX, 1040NR, 1040EZ, 1040A and 1040. The amended form can only be filed by mail, not electronically. Form 1040X has a column for the amount you claimed on the original tax return and a column for the correct amount that should be reported. You will need a copy of the original return you submitted to the IRS to complete the amended return. If the change affects other forms or schedules, you must include an amended version of each. For instance, if you change your itemized deductions, you must send along a new Schedule A.
After making changes to the original federal tax form on the amended return, you must send the appropriate documentation along with Form 1040X. For instance, if you change your income, you must send along documentation showing the change. This may be a forgotten or corrected W-2 or 1099 form.
Statue of Limitation
You must file a separate Form 1040X for each year that you have a incorrect refund. However, you must be in the limits of the federal government's statues of limitation. If you have additional money coming back, you can only amend your federal return three years after the date of the submission of the original return. For instance, if the original tax return for 2009 was submitted on April 15, 2010, you have until April 15, 2013, to file a federal amended return. If you had an extension and filed your federal tax return on Oct. 15, 2012, you have until Oct. 15, 2015, to file the amended return.
State Amended Return
After you amend your federal tax refund, you must submit a separate amended return for your state if you are changing income, some credits, expenses and deductions. Each state has different statue of limitations and instructions for filing the amended returns.