(a) Transportation service. Remuneration paid to nonresident aliens who are residents of a contiguous country (Canada or Mexico) and who, in the performance of their duties in transportation service between points in the United States and points in a contiguous country, enter and leave the United States at frequent intervals, is excepted from wages and hence is not subject to withholding. This exception applies to personnel engaged in railroad, bus, ferry, steamboat, and aircraft services and applies whether the employer is a domestic or foreign entity. Thus, the remuneration of a nonresident alien individual who is a resident of Canada and an employee of a domestic railroad, for services as a member of the crew of a train operating between points in Canada and points in the United States, is not subject to withholding under section 3402.

(b) Service on international projects. Remuneration paid to nonresident aliens who are residents of a contiguous country (Canada or Mexico) and who, in the performance of their duties in connection with the construction, maintenance or operation of a waterway, viaduct, dam, or bridge traversed by or traversing the boundary between the United States and Canada or the boundary between the United States and Mexico, as the case may be, enter and leave the United States at frequent intervals, is excepted from wages and hence is not subject to withholding. Thus, the remuneration of a nonresident alien individual who is a resident of Canada, for services as an employee in connection with the construction, maintenance, or operation of the Saint Lawrence Seaway and who, in the performance of such services, enters and leaves the United States at frequent intervals, is not subject to withholding under section 3402.

(c) Limitation on application of section. The exception provided by this section has no application to the remuneration of a resident of Canada or of Mexico who is employed wholly within the United States as, for example, where such a resident is employed to perform service at a fixed point or points in the United States, such as a factory, store, office, or designated area or areas within the United States, and who commutes from his home in Canada or Mexico in the pursuit of his employment within the United States.

(d) Certificate required. In order for the exception to apply, the nonresident alien employee must furnish his employer a statement setting forth the employee's name and address and certifying (1) that he is not a citizen of the United States, (2) that he is a resident of Canada or Mexico, as the case may be, and (3) the approximate period of time during which he has had such status. Such statement shall be dated, shall be signed by the employee, and shall contain, or be verified by, a written declaration that it is made under the penalties of perjury. No particular form is prescribed for this statement.

(e) Effective date. This section shall not apply with respect to remuneration paid after December 31, 1966. For rules with respect to such remuneration see § 31.3401(a)(6)-1.