This week, a batch of 1.1 million stimulus check payments went out from the IRS, for more than $2 billion. But if you're still waiting for your money, know that the IRS is not done sending this third round of checks. The IRS is now up to more than 164 million payments since March's American Rescue Plan, for $386 billion. But the IRS is keeping to a weekly payment schedule for those who qualify for a payment, either through a direct deposit to your bank or in the mail. And that third check may not be all the IRS is sending you.

You could also be eligible for a "plus-up" payment -- along with the check up to $,1400 -- if the IRS underestimated your dollar amount by using an older tax return when it calculated your payment. After you get your payment, watch for a letter from President Joe Biden with information about your third check. See below for why you want to keep this confirmation letter. (You may still be waiting for your tax refund, too. Here's how to check on that using the IRS tracker.) Among the payments the IRS has cued up include checks for nonfilers -- people who don't normally file a tax return -- and for those who receive SSI and SSDI benefits.

Here's what to know about the IRS timeline for payments, including how to report a stimulus check problem and when it's time to file a payment trace. If you have kids, keep an eye out for child tax credit payments for up to $3,600 to start this summer, and how to claim up to $16,000 for child care expenses. Also, here's how to check on the status of your tax refund. In a speech last week, Biden talked about what money you could receive as part of his administration's next two stimulus proposals, beyond the American Rescue Plan, including talk of a fourth check. This story is frequently updated.

Plus-up stimulus payments sent each week along with the third round of checks

Already have the stimulus check you qualified for? The IRS may owe you a plus-up payment too. Depending on which year's tax form the IRS used when it did the math on your third payment, The IRS may have calculated the amount of your payment using an older tax form instead of your 2020 filing. If this is your situation, once the IRS receives your 2020 tax return and calculates your third payment again, under the American Rescue Plan, you could be due more money based on information from your current filing -- or on other factors if you don't usually file.

The IRS said it will automatically send these plus-up stimulus payments if it needs to square up the amount it owes you, but to double-check the math, you may want to confirm how much money you should expect this stimulus round, and then track your payment.

Should you use the IRS tracker to get an update on the status of your stimulus check?

Knowing the status of your payment is an important part of making sure you know where your full payment stands. With the IRS Get My Payment tracker tool, you can get a daily update on the status of your payment. The online app can also alert you with a message if there's a problem with your payment that you may need to address.

It can't, however, give up an update on your plus-up payment status from the IRS.

If you expect your payment is coming in the mail, you use a free tool from the USPS to track your mailed stimulus payment.

IRS stimulus check timeline through December 2021

Most of the third stimulus check payments have gone out from the IRS and US Department of the Treasury based on what information the IRS has on hand to determine payment amounts. The March stimulus law, however, gives these federal agencies until Dec. 31, 2021, to send out all the third checks. That gives the IRS room to process 2020 tax returns and square up payments for those who are owed plus-up amounts, folks who file a 2020 tax extension and other groups, like those who moved or don't have a fixed address (such as people experiencing homelessness).

If all or part of your stimulus check doesn't arrive by then, you'll need to claim missing money via a 2021 tax return in April 2022, a year from now. This would be similar to the Recovery Rebate Credit for claiming missing money from the first two checks, which is currently in effect for 2020 taxes.

Stimulus check payments made to date

	Direct deposit	Paper checks	EIP Card	Direct Express Card	Plus-up
1st payment batch -- March 17	90 million ($242 billion)	150,000 ($442 million)	Not disclosed	Not disclosed	Not disclosed
2nd payment batch -- March 24	17 million ($38 billion)	15 million ($34 billion)	5 million ($11 billion)	Not disclosed	Not disclosed
3rd payment batch, including Social Security -- April 3	2 million ($5 billion)	2 million ($5 billion)	Not disclosed	Not disclosed	Not disclosed
4th payment batch, including first plus-up payment -- April 7	24 million ($33 billion)	1 million ($3 billion)	Not disclosed	3.1 million	1 million ($2 million)
5th payment batch, including nonfiler veterans -- April 14	1.2 million ($2 billion)	800,000 ($1.4 billion)	Not disclosed	Not disclosed	700,000 ($1.2 billion)
6th payment batch -- April 21	900,000 ($1.5 billion)	1.1 million ($1.8 billion)	Not disclosed	Not disclosed	700,000 ($1.2 billion)
7th payment batch -- April 28	1.1 million ($2.5 billion)	850,000 ($1.8 billion)	Not disclosed	Not disclosed	730,000 ($1.3 billion)
8th payment batch -- May 5	600,000 ($1.1 billion)	500,000 ($900 million)	Not disclosed	Not disclosed	570,000 ($1 billion)

Hold on to that Biden stimulus letter from the IRS

Keep that letter the IRS is sending you from Biden that confirms your stimulus payment, including the amount. That IRS letter -- officially called Notice 1444-C -- is your proof the IRS sent a payment in case you don't actually receive it or if you received less than you qualify for and need to claim the missing amount later. Here's more on what to do with that IRS letter.

The IRS may owe you money from the first and second stimulus checks

Plus-up payments are going out weekly along with the third round of checks, but they may not be the only money you're due. For money missing from the first two checks, you need to claim that on your 2020 taxes. You have until Tax Day to do that, which in 2021 is May 17. We suggest making sure you also know where to find your adjusted gross income. Tax nonfilers may need to be proactive about claiming a new dependent, too.

What if you have a problem with your stimulus payment? Start here to see an update on its status

The IRS doesn't want you to call if you have any issue with the delivery or amount of your stimulus check. So what to do instead? Our guide walks you through how to report stimulus check problems, including checks that never arrived (try filing a payment trace), direct deposit payments that go to the wrong account and other issues.

Did you get less money than you expected in your check?

The IRS isn't particularly big on communicating how much money it calculates for your stimulus check. You won't find that figure in the agency's