This year is a complicated one for me for tax purposes. I've been in the US since mid 2015, with F1 status. I currently still have F1 status, with OPT.
If I've understood everything correctly, I passed the substantial presence test for tax residency last month in July. Does this mean that I am a tax resident in 2020 from July onward, or for all of 2020, or from when I first entered the US this year (I've been in the US for pretty much the entire year, except that over the new year break I was in Canada, and returned to the US on Jan 3)? In particular, next year, for 2020, should I file as resident or dual-status?
My employment this year will have been as follows. Jan-Apr: I worked for Employer A. Jun-Dec: I will have worked for Employer B. Employer A did not withhold FICA taxes, because I was a non-resident on F1. If I file as a resident, will I need to pay these taxes at tax time next year?
In July, I got married. My wife is a Canadian citizen. By the end of this year, she will have been in the US for about 5 months, from August onward. For 2020, will we be able to file jointly?