What is Form 1040X?

Mistakes happen, and the IRS understands that (though the jury is still out regarding how forgiving the IRS is about mistakes). For this reason, the IRS provides the Form 1040X, which requires a line-by-line description of any necessary adjustments, as well as supporting documentation and explanations.

How Does Form 1040X Work?

Let's say John Doe files his tax return on April 15. After he sends the return in, he realizes he forgot to include some dividend income on his tax return and has understated his tax liability. So, he files a Form 1040X to inform the IRS that he is amending his return.

Why Does Form 1040X Matter?

A Form 1040X is a tax form used to amend a previous tax return.

Ask an Expert about Form 1040X

All of our content is verified for accuracy by Paul Tracy and our team of certified financial experts. We pride ourselves on quality, research, and transparency, and we value your feedback. Below you'll find answers to some of the most common reader questions about Form 1040X.

Be the first to ask a question

If you have a question about Form 1040X, then please ask Paul.

Ask a question
Paul Tracy
Paul Tracy

Paul has been a respected figure in the financial markets for more than two decades. Prior to starting InvestingAnswers, Paul founded and managed one of the most influential investment research firms in America, with more than 3 million monthly readers.

Verified Content You Can Trust
verified   Certified Expertsverified   5,000+ Research Pagesverified   5+ Million Users