Resident/NonResident OPT Medicare SS
Dear Expert, here I have two questions regarding my tax status.
I came here to the United State in Aug 2000, so technically this is my 5th calendar year, I believe I should file as a Resident on tax purpose. However, because I am still working on OPT, my company's payroll says I do not need to pay SS and Medicare, even after I told them that this is my 5th year. So I am wondering is it my responsibility or my company's that I didn't pay SS and Medicare? Am I considered as resident on tax purpose?
Also, I filed jointly as resident with my husband last year because he is on H1B, so I am wondering does that affect that I need to pay SS and Medicare as well? Can I file separately as non-resident if applicable?
In a word, I am wondering what shall I do with my SS and Medicare? Shall I pay for it? What if I don't? Thanks for your advice.