I was working on H1B visa in the U.S from 2017 to 2021, I left the U.S in June 2021 and went to Canada to get together with my wife and we married in October there. Currently, I'm trying to get my 2021 tax return, and based on my understanding, I lived for more than 31 days in the U.S in 2021 and more than 183 days in the previous 3 years so I should still be considered as Resident Alien for tax purpose even though I have left the country.
Since I'm married I could do either Married file separately or Married file jointly, both of those methods require paper filing and my spouse has an ITIN number. My question is when I hand my tax documents together with the application for ITIN, what exact tax documents do I need to submit, like the original W-2 form etc., or the calculated tax return form of some kind? Also, do I need to submit my wife's income tax document in Canada to IRS? thanks.
