FERS Report.com

Methodology

This page lists the formulas and assumptions used by the calculator. Your agency and OPM make the official retirement determination. Report an error to support@fersreport.com.

1. Basic annuity

Gross annuity = multiplier × high-3 × years and months of service used in the computation.

  • Multiplier is 1.0%, or 1.1% when retiring at age 62+ with 20+ years of service.
  • For a qualifying special-provision retirement, the formula uses 1.7% for up to 20 years of covered service and 1.0% for other creditable service, covered service over 20 years, and sick-leave credit. Special coverage and eligibility depend on the employee's position and service record.
  • For an immediate annuity, unused sick leave converts at 2,087 hours = 1 year and can increase the computation. It cannot establish eligibility. Unused sick leave is not credited in a deferred annuity.

2. Eligibility & the MRA table

Immediate unreduced: MRA + 30, 60 + 20, or 62 + 5. MRA+10: at MRA with 10–29 years, reduced 5% per year under 62 (5/12% per month). VERA applies only when an agency has authority and offers it to the employee: 50 + 20 or any age + 25, with no FERS age reduction. Deferred: 5+ years, payable at 62 (5–19 yrs), 60 (20–29 yrs), or MRA (30+ yrs).

MRA by birth year: 1947 or earlier → 55; 1948–1952 → 55 + 2 months per year; 1953–1964 → 56; 1965–1969 → 56 + 2 months per year; 1970 or later → 57.

3. Special retirement supplement

Estimated supplement = age-62 Social Security benefit × ((rounded years of FERS civilian service, capped at 40) ÷ 40). For an eligible immediate unreduced retirement, the supplement ends around age 62 under OPM's month-of-entitlement rules. An eligible VERA retiree starts receiving it at MRA. It is not payable under MRA+10 or deferred retirement. Sick leave does not count toward the supplement.

Earnings test (2026): the supplement is reduced $1 for every $2 of wages or self-employment income above $24,480. For retirees who receive the supplement before MRA under special retirement provisions, the earnings test begins at MRA. The calculator applies planned earnings directly; OPM generally bases a year's reduction on earnings from the prior year.

4. Survivor elections

Full survivor benefit: survivor receives 50% of your annuity; costs 10% of your annuity. Partial: 25% benefit, costs 5%.

5. COLAs in projections

Regular FERS annuities receive no COLA before age 62. From 62, the FERS "diet COLA": CPI ≤ 2% → full CPI; 2–3% → 2%; above 3% → CPI − 1%. You set the assumed CPI (default 2%); Social Security is adjusted at the full assumed CPI. All projections are in nominal dollars.

6. TSP projection

Balance grows at your assumed rate with annual contributions until separation; income uses your chosen withdrawal rate (default 4%) on the balance at retirement. This is a planning approximation, not investment advice or a Monte-Carlo simulation.

7. What the calculator does not model

  • Part-time service proration, military deposits, and refunded-service redeposits — these change your official computation; ask HR for a certified estimate.
  • Agency determinations of special-provision coverage or eligibility.
  • FERS-RAE/FERS-FRAE contribution differences (they change what you pay in, not the annuity formula).
  • Taxes — federal/state treatment varies; bring the report to your tax preparer.
  • CSRS and CSRS-Offset.

8. Sources

Constants version: 2026 (earnings limit $24,480). We update constants each year when SSA/OPM publish new figures.

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