Deciding when to claim Social Security — 62, full retirement age, 70, or anywhere in between — is one of the most consequential financial decisions most retirees make, and it's driven almost entirely by a break-even calculation most people never actually run. The gap between claiming early and claiming late is bigger than most people expect, and the right answer depends on a factor nobody can know for certain in advance: how long you'll live.
The size of the gap
Social Security's reduction and credit formulas are permanent, not temporary. For someone with a full retirement age (FRA) of 67, claiming at 62 — the earliest possible age — reduces the monthly benefit by 30% compared to what they'd get at FRA. Waiting until 70 — the latest age delayed credits keep accruing — increases the monthly benefit by 24% above the FRA amount. Between those two extremes, that's roughly a 43% difference in monthly benefit for the exact same lifetime earnings record, simply based on when you start collecting.
The break-even math, worked through
Say someone's FRA benefit is $2,000/month. Claiming at 62 gives them $1,400/month (30% reduction) starting immediately. Claiming at 70 gives them $2,480/month (24% increase) but starting 8 years later. Over those first 8 years, the age-62 claimer collects roughly $134,400 that the age-70 claimer collects nothing. From age 70 onward, the age-70 claimer collects $1,080 more per month than the age-62 claimer — it takes roughly 124 months (about 10.3 years) of that $1,080/month gap to make up the $134,400 head start, putting the break-even point at around age 80. Live past 80, and delaying to 70 produced more total lifetime income; die before 80, and claiming at 62 did.
Why there's no single right answer
The break-even calculation only tells you the crossover point — it doesn't tell you which side of it your own life will land on. Someone with a family history of long lifespans, good personal health, and other income sources to bridge the early years might reasonably lean toward delaying. Someone who needs the income immediately, has health concerns, or comes from a family with shorter typical lifespans might reasonably lean toward claiming earlier, even knowing the math favors delaying IF they live long enough. Both are legitimate, individually rational choices — this is genuinely a case where there's no universally correct answer.
Common mistakes
Treating the decision as purely a longevity bet while ignoring current financial need is the most common mistake — someone who needs the income at 62 doesn't have the luxury of waiting purely for a better break-even outcome years later. The second is forgetting the reduction and increase are PERMANENT — they apply for the rest of your life once you claim, not just for a few years. The third is not accounting for a spouse's benefit in the decision — for married couples, the higher earner's claiming age can also affect the survivor benefit the lower earner may eventually receive, adding a dimension the simple break-even math above doesn't capture.