Hi
I came to US on a F1 Visa in August 2006. I Started my OPT from Dec 2008, and I got my H1b Visa in October 2010. My Employer has not been deducting SSNa and Medicare Taxes, since I was in OPT. My Employer started deducting my taxes from January 1st. Should I pay the SSN taxes from October when I file my Taxes? My H1B has not yet been stamped, and my OPT is valid till May 2011. Can I file it with Status as F1?

Thanks

The day your H-1B visa became effective (probably 1 October 2010) is the day you LOST F-1 visa status and became liable for FICA (Social Security and Medicare) taxes. The STAMPING of your visa has NOTHING to do with the effective date of the visa, which is on the approval notice.

It seem apparent that your employer either did not know this, or did not care enough to correct the mistake. In either case, YOU have the legal obligation to notify your employer that you WERE liable for FICA taxes starting on 1 October 2010. You should make this notification IN WRITING; email is good for this, and print off a DATED copy of the email and retain it in your records.

After that, it is up to your employer to correct the error and come back to you to collect YOUR share of the FICA tax from your salary. If he fails to do so, the IRS will NOT bother YOU about those back taxes, but will deal ONLY with the employer. The IRS position in this matter is clear: the EMPLOYER is SOLELY responsible to pay the FICA taxes owed, and to collect the employee's share from his/her salary. If the employer fails to do so, the IRS goes to the EMPLOYER and expects FULL payment ONLY from the employer.

Further, if the employer waits until AFTER 31 January 2011 to attempt to collect back-due FICA taxes from the employee, it is my opinion that the employer loses ALL LEGAL STANDING to collect the back taxes. Of course, if they want to collect and you do NOT cooperate, you would likely LOSE your job, but they could NOT legally collect these taxes from you if you decide not to cooperate.