Did you get the right stimulus check amount? Why you need to know before filing your tax return

Americans who have not received their coronavirus stimulus check payments, or who received the incorrect amount, have an opportunity to claim the missing money now that the 2020 tax season is officially underway.

The first stimulus check was based on either your 2018 or 2019 tax return, while the second check was based on your 2019 return. But millions of Americans lost their jobs, or saw their income reduced, last year as a result of the pandemic -- meaning that many individuals who didn't initially receive the money based on their 2018 or 2019 tax returns may now qualify.

If you think the IRS owes you stimulus money, you can use a recovery rebate worksheet to calculate how much you should receive and claim that amount on Line 30 on your 2020 tax return. The IRS will include your stimulus payments as part of your refund check.

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It's worth double-checking to see how much money the federal government should have sent to you as part of its coronavirus relief efforts: You can use this free stimulus check calculator from Omni to determine how much money you should have received from the first payment, and use this calculator to see how much you should have received from the second payment.

The CARES Act, passed in March, provided cash payments of up to $1,200 for adults ($2,400 for couples filing jointly) and $500 per child under 17. And the $900 billion coronavirus relief package, approved at the end of December, authorized additional payments of up to $600 per adult ($1,200 for couples) and up to $600 for each qualifying child under 17.

The Internal Revenue Service headquarters building appeared to be mostly empty April 27, 2020 in the Federal Triangle section of Washington, DC. (Photo by Chip Somodevilla/Getty Images)

The IRS opened up Free File, free online tax preparation software, for taxpayers who earn less than $72,000 to prepare and file their income tax returns. Americans can also claim their stimulus check using the tool.

"You have nothing to lose by filing a tax return for your stimulus payment. The credit won't increase your taxes or reduce your refund. The second stimulus payment can't be seized by creditors or garnished by the government for nonpayment of child support," AARP said. "And, the IRS says, if your adjusted gross income is less than $72,000, you can use its Free File service at no charge to calculate your credit and file a tax return electronically."

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