How can I fix a mistake I made on my income tax filing? [US]

Question

How can I fix a mistake I made on my income tax filing?

Answer 1

Depending on your mistake, you probably need to file an amended return (called a "1040X" form).

http://www.irs.gov/taxtopics/tc308.html

http://www.irs.gov/newsroom/article/0,,id=108657,00.html

The above pages include links to the 1040X PDF form, and the instructions for it.

If you filed with TurboTax, it supports the ability to do a 1040X (not sure about TaxCut, etc).

Note that you have to print/mail the 1040X form, you can't e-file it.