Visa and greencard

[newresident]

Good afternoon,

in the past (2016/2017/2018) tax years I filed taxes as a J1 visa holder and Au Pair. 
In 2021 I entered the US at the beginning of January with a student F1 visa and in September I became a green card holder. Technically I pass the presence and the greencard holder tests. But I want to make sure I can file my taxes as a resident. Thank you.

[DanaB27]

It seems as if you became a resident in September because you were exempt from the substantial presence test while you were on the F1 visa. It seems as if you might have a dual status for 2021. Please see How should I file my taxes as a dual-status alien?

"If you meet the green card test at any time during the calendar year, but do not meet the substantial presence test for that year, your residency starting date is the first day on which you are present in the United States as a lawful permanent resident." (IRS)

[newresident]

Thank you so much for replying.

If I was in the US for the whole year of 2021 I still don’t pass the substancial presence test? 

[DanaB27]

You stated you were on a F1 visa at the beginning of the year, therefore the days while on the F1 visa were exempt from the substantial presence test.

[newresident]

Oh! I read that wrong, I read it was all days. Thank you for clearing that up. 
I was very excited because it seemed I was gonna get the stimulus now.