After you file

It depends.  You may be entitled to a Recovery Rebate Credit. This credit is intended to give you a credit for the stimulus payment you should have received but never actually received.  

If the credit amount exceeds your tax liability, you could still get a portion of your stimulus refunded to you on your tax return but it would be shown as the Recovery Rebate credit instead of as a stimulus payment.

Please see the attached link for more information on who can claim the credit.

Recovery Rebate Credit eligibility

When you complete your 2020 income tax return, there is a section at the beginning of the Federal Review section that will ask you about your stimulus payment.

This will take you to the input section for the Recovery Rebate credit.

Be sure to indicate the actual amount of each stimulus payment you received on the page that asks if you received a stimulus payment.  There will be two boxes and both need to be completed.  If you did not receive any stimulus payments, please indicate We didn't get a stimulus payment by checking that box.