If you are an international student nonresident for tax purposes, you are NOT subject to Social Security and Medicare taxes if any of the following applies to you:

• you have on campus employment
• you are authorized for Curricular or Optional Practical Training
• you are authorized for employment due to economic hardship

If your employer has withheld Social Security and Medicare tax in error, follow these steps:

• Request a refund for these taxes from your employer
• If your employer  agrees to refund these taxes, you do not need to file Form 843
• If your employer is unable to refund these taxes, file Form 843 and Form 8316 to request a refund from IRS.

International students nonresident for tax purposes are NOT subject to Social Security and Medicare taxes.

According to Internal Revenue Service Publication 519, U.S. Tax Guide For Aliens, services performed by ... a nonresident alien temporarily in the United States as a nonimmigrant under subparagraph “F”, “J”, “M” or “Q” of section 101(a)(15) of the Immigration and Nationality Act are not covered under the social security program if the services are performed to carry out the purpose for which ... (the nonresident) ... is admitted to the United States.

This means that there will be no withholding of social security or Medicare taxes from the pay ... (the nonresident)... receive(s) for these services. ....these types of services are very limited, and generally include only on-campus work, practical training, and economic hardship employment.

If taxes are withheld in error, the employee is entitled to a refund. The employee is first instructed to contact the employer for a refund.

In addition, according to IRS Publication 519, if the employee is unable to get a full refund of the amount from (the) employer, (the employee) should file a claim with the Internal Revenue Service on Form 843, Claim for Refund and Request for Abatement, and attach a copy of the form W-2, Wage and Tax Statement, to prove the amount of Social Security and Medicare taxes withheld.

If your employer has deducted Social Security and Medicare taxes from your W-2 and you qualify for all the requirements mentioned above, you can file 2007 Form 843 to request a refund for the taxes withheld in error by your employer.The 2007 Form 843 should be mailed at the same IRS office where you have mailed your tax return for the period you are claiming a refund.