26 CFR § 31.3401(a)(8)(C)-1 - Remuneration for services performed in Puerto Rico by citizen of the United States.
(a) Remuneration paid for services performed within Puerto Rico for an employer (other than the United States or any agency thereof) by a citizen of the United States does not constitute wages and hence is not subject to withholding, if it is reasonable to believe that during the entire calendar year the employee will be a bona fide resident of Puerto Rico. The reasonable belief contemplated by section 3401(a)(8)(C) may be based upon any evidence reasonably sufficient to induce such belief, even though such evidence may be insufficient upon closer examination by the district director or the courts finally to establish that the employee was a bona fide resident of Puerto Rico for the entire calendar year.
(2) In any case where the employee files with the employer a statement (containing a declaration under the penalties of perjury that such statement is true to the best of the employee's knowledge and belief) that such employee has at all times during the current calendar year been a bona fide resident of Puerto Rico and that he intends to remain a bona fide resident of Puerto Rico during the entire remaining portion of such current calendar year.
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