President Joe Biden signed the $1.9 trillion Covid-19 relief package into law Thursday afternoon.

The legislation, known as the American Rescue Plan, includes a number of forms of pandemic-related assistance, including a third round of stimulus checks worth up to $1,400 for individuals and up to $2,800 for married couples, plus an additional $1,400 per eligible dependent, with no cap on the number of dependents claimed.

Stimulus checks could start hitting bank accounts "as soon as this weekend," White House Press Secretary Jen Psaki said during a press conference Thursday.

Here's who qualifies for a third stimulus check under the pandemic relief package, and how to calculate how much you could get.

Income eligibility for third-round stimulus checks

Like the previous two rounds of stimulus checks, the IRS will use your latest tax return to determine stimulus check eligibility.

Video by Stephen Parkhurst

The bill calls for $1,400 payments per individual, or $2,800 for married couples, provided they fall under certain income thresholds.

Individuals with up to $75,000 in adjusted gross income will qualify for full payments, as well as heads of household earning up to $112,500 and married couples who file jointly with up to $150,000.

The checks would be reduced for incomes above those thresholds and capped at $80,000 in income for single filers, $120,000 for heads of household, and $160,000 for joint filers.

More adults could qualify for checks

The biggest difference in the latest round of stimulus checks is the change in dependent eligibility. Under the law, dependents stand to receive $1,400 each, which is more than twice the amount they qualified for in previous rounds. That means an eligible family of four would receive $5,600.

And, unlike the previous two rounds, dependents over age 16 would be eligible for aid. That means parents or caretakers who claim a dependent on their taxes who is older than 16 would receive a check for $1,400 per dependent.

A previous report from the American Enterprise Institute estimates that as many as 26 million more people will now be eligible for a payment because of the change in dependent eligibility.

Use the calculator below to calculate how much stimulus money you could be eligible for.

File early and electronically

Since eligibility will be based on 2020 or 2019 taxes, taxpayers may want to consider filing early, according to Janet Holtzblatt, senior fellow at the Urban-Brookings Tax Policy Center. "People whose income fell in 2020 should file early and file electronically in order to increase their odds of quickly getting a direct payment that reflects their circumstances during the pandemic," Holtzblatt says.

If you were eligible for any stimulus money, but didn't receive some, or all of it, filing your 2020 taxes will give you the opportunity to claim the aid as a tax credit when you file, she explains.

Now that Biden has signed the bill into law, the vast majority of Americans should begin to receive a third round of stimulus checks quickly. "This plan will get checks out the door, starting this month, to the American people who so desperately need the help," Biden said in prepared remarks last weekend.

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