Form 1040X

Written By
Paul Tracy
Updated November 4, 2020

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.

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