After you file

Did you get the first or second Stimulus payment?  And enter the amounts you got?

 

Yes you can see your refund or tax due change when you enter the Stimulus payments.  Your 2020 return starts out by assuming you didn't get any Stimulus payments so it gives you credit for the full amount.  Then near the end you enter how much you actually got so it only gives you the difference if any.  You don't get it twice.