I am a Canadian citizen living and working in the U.S. for a U.S. employer on a visa. Do I need to file both a U.S. tax return and a Canadian tax return?

You must comply with both U.S. and Canadian filing requirements, if any. In the United States, you generally are required to file a return if you have income from the performance of personal services within the United States. However, under certain circumstances, that income may be exempt from payment of U.S. tax pursuant to the U.S.-Canada income tax treaty. You need to determine what type of visa you have, and how that impacts your residency status in the United States. If, based on the tax code and your visa status you are treated as a U.S. resident, then your entitlement to treaty benefits will be impacted. You must contact the Canadian government to determine whether you must file a Candian tax return and pay Canadian taxes.

Under my visa as a temporary nonresident alien, I'm not subject to social security and Medicare withholding. My employer withheld the taxes from my pay. What should I do to get a refund of my social security and Medicare?

If social security tax and Medicare were withheld in error from pay received which was not subject to the taxes, you must first contact the employer who withheld the taxes for reimbursement. If you are unable to get a refund from the employer, file a claim for refund with the Internal Revenue Service on Form 843 (PDF), Claim for Refund and Request for Abatement.

You must attach the following to your claim:

a copy of your Form W-2 (PDF), Wage and Tax Statement, to prove the amount of tax withheld;

Form I-797, INS Approval Notice, is needed if you have changed your status from F-1 or J-1 to another status prior to filing the claim;

if your visa status changed during the tax year you should attach copies of the pay stubs that cover the period of exemption from social security taxes;

a copy of INS Form I-94, Arrival/Departure Record, if you are still in the United States;

a copy of your valid entry visa;

Form 8316, Information Regarding Request for Refund of Social Security Tax, , or a signed statement stating that you have requested a refund from the employer and have not been able to obtain one; and

a copy of Form 1040NR (PDF) , US Nonresident Alien Income Tax Return (or Form 1040NR-EZ (PDF)), for tax the year in question. Processing of your claim may be delayed if you submit it less than six weeks after you filed Form 1040NR or 1040NR-EZ.

In addition to the documentation listed above foreign student visa holders should also attach the following:

a copy of Form I-20, Certificate of Eligibility, endorsed by your student advisor and stamped by the Bureau of Citizenship and Immigration Services; and

a copy of the Employment Authorization Document of your Optional Practical Training (e.g., Form I-766, I-538 or 688B).

if you are an exchange visitor, attach a copy of Form IAP-66 or DS-2019 to your claim.

File the claim, with attachments, with the IRS where the employer's returns were filed. If you do not know where the employer's returns were filed, send your claim to the Internal Revenue Service Center, Philadelphia, PA 19255.

For more information, refer to Publication 519, U.S. Tax Guide for Aliens .

Are nonresident alien students, with F-1 or J-1 visas and employed by a U.S. company during the summer, required to have federal income taxes withheld from their paychecks?

The following discussion generally applies only to nonresident aliens. Wages and other compensation paid to a nonresident alien for services performed as an employee are usually subject to graduated withholding at the same rates as resident aliens and U.S. citizens. Therefore, your compensation, unless it is specifically excluded from the term "wages" by law, or is exempt from tax by treaty, is subject to graduated withholding. Nonresident aliens must follow modified instructions when completing Form W-4. Please refer to Publication 519, U.S. Tax Guide for Aliens, for directions on completing Form W-4 (PDF), Employee's Withholding Allowance Certificate.