The No. 1 factor that lowers your monthly Social Security check. Get it right in 2026

But not all factors are equally weighted. Some have a much larger impact — and one, in particular, could be considered make-or-break: the age at which you file your claim.

Instead of stressing about ways to boost your earnings late in your career or extending your career by a few years, you can often meaningfully increase or reduce your monthly benefit simply by timing your claim strategically.

Here’s why this factor dominates.

Numbers don’t lie: patience is rewarded

When you run the numbers on the SSA’s own benefits planning calculator, it becomes obvious that claiming age often has the single largest impact on monthly benefits (1).

Consider this: someone entitled to $2,000 per month at full retirement age (67 for those born in 1960 or later) faces very different outcomes based solely on when they file.

Claim at 62, the earliest possible age, and that $2,000 shrinks to just $1,400 — a permanent 30% reduction (2). Wait until age 70, and the same benefit rises to $2,480, a 24% increase over full retirement age (FRA).

The gap is significant. By waiting from 62 to 70, this person increases their monthly benefit by roughly 77% compared with claiming at 62.

To be clear, claiming age does not need to coincide with retirement age. A person could retire at 62 or 67 and use personal savings to cover expenses while delaying benefits, thereby locking in a higher lifetime monthly payment.

However, delaying is not always more effective than working additional years; in some cases, replacing low-earning years in the 35-year calculation can also meaningfully increase benefits.

How claim age stacks up against other factors

To put into perspective just how important claiming age really is, let’s compare it to another factor that many planners would consider critical: work history.

The SSA uses your 35 highest-earning years, adjusts those earnings for inflation, and averages your Average Indexed Monthly Earnings (AIME) (3). Your AIME is then used in a formula to determine your primary insurance amount (PIA), which is the benefit you’d receive at full retirement age.

If your career is shorter — say 30 years — the SSA includes five years of zero earnings in the 35-year calculation, which lowers your average and reduces your benefit. But the impact may be smaller than claiming early, depending on your earnings history.

For example, suppose Jamie was born in 1971 and worked from 1991 through 2025, earning a steady $50,000 per year (before indexing). Using SSA formula estimates (not exact calculator results), his projected monthly benefit at full retirement age might be about $3,234. If he had stopped working five years earlier, five $0 years would be included in the calculation, reducing his estimated benefit to roughly $3,087.