While many Americans are looking ahead to see if they will be eligible for a third COVID-19 related stimulus check from the government, others are still trying to figure out how to claim funds they missed out on during the first two rounds. However, even with the IRS saying they have sent out all eligible checks, those who believe they are still owed money will have a chance to get it.

The IRS said it had sent out more than 160 million checks for the first round of stimulus check payments from April 2020 and more than 147 million additional checks for the second round in December, CBS News reports. Those who missed out on payments, either because they didn’t earn enough money to file tax returns in previous years or lacked bank accounts, are still able to claim the money they are owed if they file a 2020 tax return.

They are able to do this through the Recovery Rebate Credit, and can only claim it when they file their taxes for 2020. To determine if money is owed—either partial or in full—those wishing to use it can use a worksheet from the IRS on their website, which will help them determine their eligibility and what they are owed. After completing it, if they learn they are owed more money, they can enter that amount on line 30 of their Form 1040.

Any extra money will then be included with their tax refund once it is accepted by the IRS, and funds should be in their accounts within 21 days.

It is unclear how filing taxes with the Recovery Rebate Credit could affect those using it for the planned third Stimulus payment, which Democrats are including in a large package that they plan to pass through Congress via Budget Reconciliation, which lowers the threshold of votes needed in the Senate from 60 to 50, avoiding Senate filibusters and, because of the narrow majority Democrats hold due to a 50/50 split there, giving the package a chance to pass with zero Republican support.

Kiplinger reports that depending on when 2020 taxes are filed, they could be used to determine the eligibility an individual has for the planned $1,400 check. If their taxes are not filed by the time payments are being processed, the information will once again revert to the 2019 tax return.

stimulus check Economic stimulus checks are prepared for printing at the Philadelphia Financial Center on May 8, 2008, in Philadelphia. Photo: Jeff Fusco/Getty Images