20 CFR §222.24

1. (a)New eligibility. A claimant will have the relationship of a remarried widow(er) if he or she is the widow(er), as discussed in § 222.11, of an employee and the claimant—
   1. (1)Remarried after attaining age 60, or remarried after attaining age 50 and after the date on which he or she became disabled; or
   2. (2)Remarried before attaining age 60, but is now unmarried, or remarried before attaining age 50 or before the date on which he or she became disabled, but is now unmarried.
2. (b)Reentitlement. A claimant will have the relationship of a remarried widow(er) if he or she remarries after his or her entitlement to an annuity as a widow(er) has been established, and the claimant—
   1. (1)Remarries after attaining age 60, or remarries after attaining age 50 and after the date on which he or she became disabled; or
   2. (2)Is entitled to an annuity based upon having a child of the employee in care and remarries, but this marriage is to a person who is entitled to a retirement, disability, widow(er)'s, mother's, father's, parent's, or disabled child's benefit under the Railroad Retirement Act or Social Security Act.