This Is the Best Age to Claim Social Security Benefits for Couples, According to a Recent Study
Social Security is often the largest source of income in retirement, so maximizing benefits can dramatically improve living standards in later life. For that reason, starting Social Security at the right time is of monumental importance, as the claiming age has a material impact on benefit payments.
While eligibility for Social Security begins at age 62, workers aren't entitled to their full benefit, or primary insurance amount (PIA), until full retirement age (FRA). Workers who claim Social Security before FRA will get a smaller benefit for life, meaning their PIA will be permanently reduced by a predetermined percentage. Similarly, workers who delay Social Security beyond FRA will get a bigger benefit for life, though there is no advantage to claiming later than age 70.
For married couples, the math becomes more complicated because claiming decisions also impacts spousal benefits. Specifically, a spouse can collect benefits on the work record of their retired partner instead of their own, provided their partner has started taking Social Security. In that scenario, the spousal benefit will equal half of the retired partner's PIA if they claim at FRA, but the payout will be reduced for spouses who claim earlier.
Source Fool.com