20 C.F.R. § 416.1830
We will stop considering you and your spouse an eligible couple, even if you both remain eligible, at the beginning of whichever of these months comes first—
[45 FR 71795, Oct. 30, 1980. Redesignated at 46 FR 29211, May 29, 1981; 46 FR 42063, Aug. 19, 1981, as amended at 60 FR 16376, Mar. 30, 1995]