FERS Supplement Calculator
Estimate your FERS annuity supplement — the bridge payment for federal employees who retire before 62. Uses the OPM estimating formula (your age-62 Social Security benefit × FERS service ÷ 40), applies the annual earnings test, and shows exactly why the supplement ends at age 62.
Works offline — your inputs never leave this device. How that works
The supplement is paid with immediate unreduced FERS retirements before 62 and always stops at 62. Earnings-test reductions are applied to future payments after an annual survey.
Verified 2026-07-30 against OPM — FERS computation, eligibility, creditable service & annuitant pamphlet (effective 2026-01-01)
Verified 2026-07-30 against SSA — 2026 COLA information + OACT bend points + 20 CFR 404.621 (effective 2026-01-01)
Estimate only — not legal, financial, or benefits advice. Only OPM can determine your actual benefit.
Official source: OPM — FERS annuity supplement ↗
🎓 Understand this tool
What it is
An estimator for the FERS annuity supplement — the payment that bridges the gap between an immediate unreduced FERS retirement before 62 and the start of Social Security eligibility.
How it works
It applies OPM's estimating method: your estimated Social Security benefit at 62, multiplied by your years of civilian FERS service divided by 40. The earnings-test check compares your expected wages against the verified annual exempt amount; earnings above it reduce the supplement $1 for every $2 over.
Getting the most from it
- Get your age-62 benefit estimate from your Social Security statement (ssa.gov) — the tool links where to find it.
- Enter your civilian FERS years only; bought-back military time does not count for the supplement.
- If you plan to work in retirement, enter expected earnings to see the earnings-test effect.
- Note the hard stop at 62 in the timeline readout.
Reading your result
The supplement is a bridge, not a bonus — it approximates the Social-Security-shaped hole in your income between retirement and 62. If the earnings test wipes most of it out, the reduction applies to future payments, not as a clawback.
What it can't tell you
Only OPM computes the actual supplement, using its own Social Security estimate, and eligibility rules (immediate unreduced retirements; special provisions differ) are more detailed than any estimator can capture.
Frequently asked questions
OPM's estimating method takes your estimated Social Security benefit at age 62 and multiplies it by your years of civilian FERS service divided by 40. Military time bought back does not count toward the supplement.
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