Is there any last date to file Form 843(to claim Social and Medicare taxes that have been withheld while on OPT)?

Thanks,

I am not sure, but logically the statutory limit applied to applying for a federal income tax refund should apply here.

If that is the case, today (15 April 2005) is the last day you can ask for a refund for improperly-withheld Social Security and Medicare taxes from calendar year 2001.

After today, only calendar years 2002, 2003 and 2004 are eligible for refunds.