How do final average salary and high-3 years affect a Representative or Senator’s pension after 10, 20, 30, and 40 years?
Executive summary
Congressional pensions are built from two moving pieces: the retiree’s “high‑3” average salary (the highest average pay over any three consecutive years) and a years‑of‑service accrual rate that differs by plan (FERS for most members since 1984; CSRS for those still covered) — the pension equals the high‑3 multiplied by the accrual factor derived from years served and the plan formula [1] [2]. Using the statutory accrual rates, a hypothetical high‑3 of $174,000 produces markedly different lifetime starting annuities at 10, 20, 30 and 40 years under FERS versus CSRS, and legal limits and age/service eligibility affect when and whether those amounts are payable [3] [4] [5].
1. How pensions are computed: the “high‑3” and accrual rates
Pension benefits for Members of Congress are calculated from three inputs: the retiree’s average annual salary for the three consecutive years of highest pay (the “high‑3”), the total years of creditable service measured in months, and the accrual rate that converts years of service into a percentage of that high‑3 salary [2] [1]. Under FERS the widely cited formula for Members is 1.7% of high‑3 for each year for the first 20 years and 1.0% for each year thereafter (though some sources note adjustments for members covered after 2012) [3] [6]. CSRS uses a higher accrual rate (historically 2.5% per year for congressional service in many CRS descriptions), and CSRS pensions are statutorily limited at retirement to no more than 80% of final salary [4] [2].
2. Ten years of service — modest starting annuity under FERS, larger under CSRS
A Member with a $174,000 high‑3 and 10 years of FERS service would have a basic annuity equal to 1.7% × 10 = 17% of the high‑3, or about $29,580 annually before any reductions for early retirement or other adjustments [3] [1]. The same 10 years under CSRS at a 2.5% accrual would yield roughly 25% of high‑3 — about $43,500 — though CSRS members are fewer and subject to different age/service eligibility rules [4].
3. Twenty years of service — the common FERS milestone and eligibility hooks
After 20 years under FERS the formula yields 1.7% × 20 = 34% of the high‑3; using $174,000 that is about $59,160 annually, and Members with 20 years may be eligible for retirement at age 50 under certain conditions or at 62 with 5 years of service depending on age/service thresholds [3] [5]. Under CSRS, 20 years at 2.5% would equal 50% of high‑3 (about $87,000), a materially higher replacement rate, reflecting the older CSRS benefit structure [4].
4. Thirty years of service — the widening gap and the 80% ceiling
At 30 years the FERS special computation (1.7% for first 20; 1.0% for next 10) produces 44% of high‑3, or roughly $76,560 on a $174,000 base [3]. CSRS at 2.5% would give 75% of high‑3 (about $130,500) but federal law limits initial CSRS pensions to no more than 80% of final salary, so very long CSRS careers approach but do not exceed that statutory cap [4] [2]. Government reports illustrate that after roughly 30 years many FERS participants reach lower replacement ratios than comparable CSRS cohorts [3].
5. Forty years of service — longer service raises FERS payouts but CSRS hits legal cap
With 40 years of congressional service the FERS arithmetic yields 34% for the first 20 plus 20% for the next 20 (1% × 20) — 54% of high‑3, or about $93,960 on a $174,000 high‑3 [3]. Under CSRS the same 40 years would mathematically be 100% at a 2.5% rate, but the 80% statutory cap on initial pensions means a CSRS retiree’s starting annuity cannot exceed 80% of final salary, so the practical CSRS ceiling (about $139,200 on a $174,000 base) governs [4] [2] [7].
6. Caveats, eligibility and competing statements in the record
These formula outputs are starting annuities before offsets, survivor elections, cost‑of‑living adjustments, or Social Security interactions; they assume the high‑3 equals $174,000 (the rank‑and‑file base salary in recent years) and that the high‑3 period is the final three years unless an earlier period is higher [1] [7]. Sources differ in nuance — CRS and OPM provide the statutory formulas and eligibility rules [2] [1] [4], GAO/agency reports illustrate comparative percentages at milestones [3], and some secondary outlets summarize examples — and readers should note that plan enrollment date (CSRS vs. FERS), leadership pay, and post‑2012 formula tweaks can change precise outcomes [6] [8].