26 CFR § 31.7701-2 — Definitions; spouse, husband and wife, husband, wife, marriage.

(a) In general. For the definition of the terms spouse, husband and wife, husband, wife, and marriage, see § 301.7701-18 of this chapter.

(b) Applicability date. The rules of this section apply to taxable years ending on or after September 2, 2016.