Treasury Regulations, Subchapter C, Sec. 31.3121(h)-1
From TaxAlmanac
Sec. 31.3121(h)-1 American employer
(a) The term “American employer” means an employer which is (1) the United States or any instrumentality thereof, (2) an individual who is a resident of the United States, (3) a partnership, if two-thirds or more of the partners are residents of the United States, (4) a trust, if all of the trustees are residents of the United States, or (5) a corporation organized under the laws of the United States or of any State. For provisions relating to the terms “State” and “United States”, see §31.3121(e)–1.
(b) For provisions relating to services performed outside the United States by a citizen of the United States as an employee for an American employer, see paragraph (c)(3) of §31.3121(b)–3 and paragraph (e) of §31.3121(b)(4)–1.
[T.D. 6516, 25 FR 13032, Dec. 20, 1960, as amended by T.D. 6744, 29 FR 8315, July 2, 1964]
