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If you still haven’t filed your 2021 tax return and never received a pandemic-era IRS stimulus check, the deadline is April 15 because there’s a three-year window to claim refunds, according to the agency.
Filers who never got the 2021 stimulus payment of up to $1,400 could claim the recovery rebate credit on that year’s return. Â
“If you didn’t get the stimulus, you’re running out of time,” said Syracuse University law professor Robert Nassau, director of the school’s low-income tax clinic.Â
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The IRS in December announced plans to automatically send “special payments” of up to $1,400 to 1 million taxpayers who didn’t claim the 2021 recovery rebate credit on tax returns for that year. Â
The agency said most payments were expected to arrive via direct deposit or paper check by late January 2025, based on the taxpayer’s 2023 tax return information.
In order to see if the IRS issued a stimulus payment, you can create an online account and view “tax records” under the “records and status” toolbar.Â
“That’s the best place to look,” said Tommy Lucas, a certified financial planner and enrolled agent at Moisand Fitzgerald Tamayo in Orlando, Florida.
Your IRS online account also shows if you filed a 2021 return, Lucas said.Â
If you don’t submit your 2021 filing by April 15, you could also miss other tax breaks, such as the earned income tax credit, which can trigger a refund even without taxes owed, according to the IRS. Â
Currently, there are more than $1 billion in unclaimed refunds for tax year 2021, the IRS estimated in early March. That represents more than 1.1 million taxpayers and a median unpaid refund of $781. These figures don’t include applicable credits, including the recovery rebate credit.

You need ‘proof’ of filing by the deadline
While there are several free options for tax returns this season, some may not offer electronic filing for 2021 returns, Nassau warned.Â
If you’re forced to mail your 2021 return, you should send the filing via certified mail for “proof” you sent it by the April 15 deadline, he said.Â
“I’ve had situations where the IRS gets something after the filing [due] date, and they just reflexively say it’s too late,” Nassau said. “Spend the $5 and send it certified.”