How this calculator works
Tax year: 2026, United States. Enter the primary insurance amount from your Social Security statement, which is the monthly benefit at full retirement age. Full retirement age is 66 for people born from 1943 through 1954, rises by two months for each birth year from 1955 through 1959, and is 67 for people born in 1960 or later. Claiming before full retirement age reduces the benefit by 5/9 of 1% for each of the first 36 months and 5/12 of 1% for each further month. Claiming after full retirement age adds 2/3 of 1% per month, which is 8% a year, up to age 70. If benefits start before full retirement age and you earn more than $24,480, $1 is withheld for every $2 above that amount, capped at the annual benefit. The model assumes a birth year of 1943 or later, uses whole claiming ages, and leaves out the year-of-full-retirement earnings limit, the monthly earnings test, cost-of-living adjustments after the first year, spousal and survivor benefits, taxes on benefits, and the windfall elimination and government pension offset rules.
Formula
Claiming factor = 1 - ((min(months early, 36) x 5/9) + (max(0, months early - 36) x 5/12)) / 100 for early claims, or 1 + months late x (2/3) / 100 after full retirement age. Monthly benefit = primary insurance amount x factor. Earnings test withholding = min(annual benefit, 0.5 x max(0, earnings - 24,480)) when claiming before full retirement age.
Worked example
A primary insurance amount of $2,000 with a full retirement age of 67 is $2,000 a month at 67. Claiming at 62 is 60 months early: 36 months at 5/9 of 1% and 24 months at 5/12 of 1% reduce it by 30%, so the benefit is $1,400. Claiming at 70 adds 36 months at 2/3 of 1%, giving 124% and $2,480.
Frequently asked questions
Where do I find my primary insurance amount?
It is printed on your Social Security statement at ssa.gov/myaccount, labelled as the benefit at full retirement age. If you have not yet worked long enough, the estimate there is the figure to use.
Does claiming early permanently reduce the benefit?
Yes. The reduction applies for the life of the benefit, apart from annual cost-of-living adjustments. Claiming later increases it permanently through delayed retirement credits up to age 70.
How does the earnings test work?
Before full retirement age, $1 is withheld for every $2 earned above the annual exempt amount. Withheld benefits are not lost forever: they are recalculated when you reach full retirement age. This page shows the current-year withholding only.
Are cost-of-living adjustments included?
No. The result is in today's dollars using the primary insurance amount you enter. Actual benefits receive annual COLAs, so future payments are normally higher in nominal terms.