It’s best to get your tax return right the first time, but mistakes happen. When they do, it may be necessary to file an amended return.
An amended return is a taxpayer’s opportunity to receive any unclaimed refund or correct an instance of underpayment after they’ve filed and the due date to file has passed.
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Why File an Amended Return
If you find a mistake in your tax return, you can submit an amended return. You generally have three years after the filing deadline to do so.
Taxpayers often amend returns because reissued or amended income forms may come later in the filing season or after the filing deadline. In addition, job changes, health issues and other life events that have tax consequences could have been overlooked.
You may also find that after the filing deadline you qualify for tax breaks you missed, which means you can amend your return to receive a refund.
“If correcting the mistake will generate a small refund, the taxpayer may not want to spend the amount a preparer would charge to fix the error,” Trish Evenstad, enrolled agent at Evenstad Tax & Financial Services in Wisconsin, says. “If the mistake generates a balance due for the taxpayer, however, it is best to file the amended return.”
Kathleen Grant, senior director, US Accountancy at IRIS Software Group agrees, adding that if the nature of the amendment is due to a more serious issue, then a call to your tax accountant may be in order. “Sometimes the goal isn’t to get a bigger refund — it’s to mitigate the audit risk and IRS notification,” she says.
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How to File an Amended Return
To amend a return, first gather relevant documents. For example, if you failed to report a portion of your income last year, you might include the omitted W-2. Then, use Form 1040-X to amend your return.
You can submit your amended return electronically or by mail, but experts suggest doing it electronically whenever possible. You can file an amended return electronically with tax filing software for the current or prior two tax years, Evenstad says.
“The IRS is becoming more electronically driven and has the ability to track and monitor changes to returns and mismatch of information faster than ever,” John P. Schultz, certified public accountant at Genske Mulder & Company in California, says.
“If you receive new information that does not match your original filing and it creates an additional liability, the IRS will come knocking on your door with penalties and interest requests in hand, so it’s always better to stay ahead of their actions and have them in your good graces,” he adds.
Tax professionals can help taxpayers respond to IRS correspondence regarding errors in previous returns, determine the tax liability implications of a newly discovered mistake, and execute the appropriate amending or superseding process.
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What to Expect When You Amend a Return
You can file an amended return within three years of the date you filed your original return or within two years after you paid any taxes you owe — but the sooner, the better.
“As soon as they discover the mistake, you should take action to correct it,” Evenstad says. “Penalties and interest are accumulating daily, so the sooner the better to fix a mistake.”
The IRS says it takes about eight to 12 weeks to process amended returns but be aware that it could take 16 weeks or longer.
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originally appeared on usnews.com
Update 04/06/26: This story was published at an earlier date and has been updated with new information.