:p Dear Madam/Sir,

I am a F1 student on OPT now. I have been in the US for 5 years. Do I have to claim as resident and pay social security / Medicare tax? Or I could still claim to be a student and do not pay the tax.

Thank you,
Cathy

Cathy:

As long as your F-1 visa is valid and you have not changed your intention regarding that visa, i.e. you will finish your OPT and will return back to your home country upon completion, then file Form 1040NR or Form 1040NR-EZ and Form 8843.

As long as you are under that F-1 visa, you are exempt from Social Security and Medicare taxes.

If you plan to stay in the U.S. after your OPT is completed, then you should apply to change your visa to H-1B status.

The day your H-1B visa status is approved is the day you start having Social Security and Medicare taxes withheld from your salary.