Based on your description, you met the substantial presence requirement in December 2021.
Because 2021 is the first year you qualify, you have the option to treat all of 2021 as U.S. resident or dual status. 2022 will be your first full year as U.S, residents.
A dual - status election for the first year works better if you had more income outside the U.S. because U.S. residents are taxed on their worldwide income. In your case, you had more U.S. income even when in nonresident status so a first year election to be treated as a resident is more simple (because you do not have to file a resident and nonresident return.
The most important factor to consider is how much non-U.S. income you had in 2021 and if it was taxes in a foreign country.
**Say "Thanks" by clicking the thumb icon in a post
**Mark the post that answers your question by clicking on "Mark as Best Answer"
