An employer may be required to withhold federal income taxes from the paycheck.  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, unless specifically excluded from the term "wages" by law, or exempt from tax by treaty.  Nonresident aliens must follow modified instructions when completing Form W-4 (PDF), Employee's Withholding Allowance Certificate. Please refer to Publication 519, U.S. Tax Guide for Aliens, for directions on completing Form W-4.  Nonresident aliens claiming a tax treaty withholding exemption for compensation should file Form 8233 (PDF), Exemption From Withholding on Compensation for Independent (and Certain Dependent) Personal Services of a Nonresident Alien Individual.