Taxpayers may need to file an amended return if the tax break makes them newly eligible for additional federal credits and deductions that weren’t already included on the original tax return, the IRS said.

For example, the unemployment tax break may make some people newly eligible for the Earned Income Tax Credit. Taxpayers who didn’t claim the credit on their initial return must file an amended return to get it. They may want to review their state tax returns, as well, the IRS said.

People who’d claimed a tax credit or deduction on their initial federal return but are now eligible for a larger tax break due to the unemployment waiver don’t have to file an amended return — the IRS can adjust it for them.