Funds were officially available Monday and will continue to go out through mid-January, according to the Internal Revenue Service.
According to the IRS, those who filed 2019 tax returns and provided direct deposit information should automatically receive the payments in their bank accounts starting Dec. 29. Those who successfully registered for the first payment on IRS.gov should also get automatic payments. But that may not be the case for everyone.
Here's what you need to know about stimulus check problems some taxpayers are facing:
What does "Payment Status Not Available" mean?
The Get My Payment tool on IRS.gov is designed to show the statuses of the first and second stimulus payments.
Remember, the payment is $600 for each eligible adult and dependent for people earning up to $75,000, or $150,000 for married couples filing jointly. Those earning more than that are eligible for a reduced payment.
Yet some people who received their first round of checks via direct deposit are getting a status that reads "Payment Status Not Available."
"We are unable to provide the status of your payment right now because we don't have enough information yet (we're working on this), or you're not eligible for a payment," the message reads.
The website's FAQ page, however, is unclear whether this status is temporary or indicates that the IRS is unable to issue a second stimulus payment. The IRS appears to be making updates to its guidance.
Those who are eligible and do not get a second COVID-19 relief check may be able to claim it when they file their 2020 taxes this year. Technically, the second stimulus check is an advanced payment of this tax credit.
Taxpayers will see unclaimed stimulus funds referred to as the Recovery Rebate Credit on Form 1040 or Form 1040-SR of their taxes. Individuals and married couples filing jointly can also claim the Recovery Rebate Credit if they did not receive the full amount of the first stimulus payment.
Click here for more information on the Recovery Rebate Credit.
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What happens if unfamiliar bank information shows up in the Get My Payment tool?
Many people said that they checked the IRS site and found their payments were sent to an account they did not recognize.
For those who receive SSA, RRB, SSI or VA benefits via Direct Express, "the bank information shown in Get My Payment will be a number associated with your Direct Express card and may be a number you don't recognize," the IRS website reads.
For those who used H&R Block to file their 2019 taxes, unfamiliar bank information may be associated with a refund transfer.
"Don't worry - we have sent these payments on to the method you chose for Refund Transfer: direct deposit, check or Emerald Card. The money should be there by the end of the day," the statement from H&R Block said.
Some TurboTax customers who paid tax preparation fees with their refunds also reported delays and funds sent to unfamiliar accounts. TurboTax said that the IRS is the "sole party with the ability to determine eligibility and distribute stimulus payments" and that by law, the financial institution must return the payment to the IRS if an account is no longer active.
There is no exact measure at this time of how many taxpayers were impacted. The IRS did not have a comment early Tuesday on the scope or cause of the problem.
Many who experienced problems with receiving their first stimulus checks also hired tax companies that used specific bank accounts to process their tax refunds, tax expert Eab Nassif said in April.
The bank numbers that these taxpayers see on the IRS's website belonged to tax preparation firms and were used to take out fees for tax prepper, Nassif said. That way, customers did not need to pay tax preppers out of pocket.
Anyone else who thinks their payment went into the wrong bank account for other reasons should first check with their bank, the IRS website reads.
If the bank says it has not received the funds and five days have passed since the deposit date, taxpayers can request a payment trace through the IRS. Click here for more information on starting a payment trace.
People should not contact their financial institutions or the IRS with payment timing questions.
What happens to people who changed bank accounts between the first and second round of payments?
According to the IRS website, the agency is only using data already in its systems by Dec. 22, 2020.
In a press release Monday, the agency said it is "exploring options to correct these payments"
Payment information cannot be changed, so these people may need to claim the payment as a Recovery Rebate Credit on their taxes.
What about address changes for those who received checks in the mail?
If you have not filed your 2019 tax return, enter your new address on your return when you file. The IRS also has forms that will notify it of an address change. Click here for more information.
The Associated Press contributed to this report.