I Made a Math Mistake on My Taxes. Do I Have to File an Amendment?

You may not have to take additional action.

So you gathered up your tax forms, copied a bunch of numbers onto your tax return, and sent it off to the IRS. Finishing your taxes is the sort of thing you can celebrate -- unless you happen to realize after the fact that you wound up making a math error.

Math errors on tax returns aren't so uncommon. After all, there's a lot of number-crunching to do, and you're only human. Mistakes are bound to happen.

You might assume that if your tax return contains a math error, you'll need to file an amendment correcting it. But generally, that won't be necessary.

The IRS will step in and help

There are certain scenarios that might warrant an amended tax return on your part. Let's say you worked a side hustle and reported the wrong amount of income. It may be that you looked through your bank account statements too quickly and failed to report some of the money you earned.

In that situation, you should prepare to file an amended tax return. Similarly, let's say you failed to claim a dependent you actually have the right to claim. That, too, is a good reason to file an amended tax return.

But you don't need to rush to file an amended return due to a problem with your math. As the IRS says on its website, "You don't have to amend a return because of math errors you made; the IRS will correct those."

Now that said, it might take the IRS longer to process your tax return if it has a math error. And that could delay your tax refund. So it's best to avoid math errors to the best of your ability.

A good way to reduce your chances of a math error

As a human being, it's conceivable that you might make a math error when filing your taxes even if you give yourself plenty of time to get the job done. But one way to lower your chances of such an error is to file your return electronically.

Because you'll be using software, a lot of the addition and subtraction you might otherwise need to do in your head or with a calculator is done for you. The result? Fewer mistakes and headaches.

One thing tax software won't do is prevent you from copying the wrong numbers onto your screen. If you're supposed to be reporting $1,492 of income from a 1099 form and you enter $1,429, your return might get questioned if the IRS sees a different number on file.

But for the most part, filing electronically is a good bet if you're worried about making a mistake. And as an added bonus, you'll generally get your tax refund much faster when you file electronically instead of on paper.

In fact, the IRS says it issues most refunds in under 21 days for filers who submit an electronic return. But if you file on paper, you might easily be waiting twice as long for the money you're entitled to.