CSRS Retirement: Pension Formula, COLA, and What Changed After the WEP/GPO Repeal

If you were hired by the federal government before 1984, you are likely covered under the Civil Service Retirement System (CSRS) — a defined-benefit pension with a more generous formula and richer inflation protection than the FERS system that replaced it. CSRS employees face a distinctive financial picture: a large pension, full CPI cost-of-living adjustments from the first payment, no employer TSP match, and — for those with private-sector Social Security earnings — a dramatically changed landscape after the Social Security Fairness Act of January 2025 repealed both the Windfall Elimination Provision and the Government Pension Offset.

This guide covers the CSRS pension formula, who qualifies, survivor annuity elections, the CSRS Offset hybrid, TSP strategy without employer contributions, and what the WEP/GPO repeal means for your retirement math.

The CSRS Pension Formula

The CSRS annuity uses a tiered multiplier applied to your High-3 average salary × creditable service years:¹

The 80% ceiling. No CSRS annuity exceeds 80% of the High-3, regardless of service length. That ceiling is reached at approximately 41 years and 11 months (10 years × tiers 1–2 producing 16.25%, plus an additional 31.875 years × 2.0% = 63.75%, totaling 80%). Continued service beyond that point adds no pension value — though it does affect the High-3 computation if your salary is still rising.

Worked Example: 30 Years, $120,000 High-3

Monthly: $5,625. Compare to a FERS employee with the same salary and service years retiring before age 62: 1.0% × $120,000 × 30 = $36,000/year — 47% less.

High-3 Average Salary

The High-3 is the average of your three consecutive highest-paid years — same concept as FERS.¹ For most full-time employees with steady step increases, this is approximately the salary 1–2 years before retirement. Part-time service years contribute at prorated pay.

Unlike FERS, CSRS has always credited 100% of unused sick leave toward the annuity computation (measured at 2,087 hours per year). A federal employee with 1,500 unused sick leave hours adds 1,500 ÷ 2,087 = 0.72 years of additional service credit.

CSRS Retirement Eligibility

CSRS retirement eligibility is simpler than FERS — no Minimum Retirement Age variable:²

No "MRA" for CSRS. The minimum retirement age concept is a FERS construct. A CSRS employee retiring at 55 with 30 years gets an immediate, unreduced annuity — no MRA+10 penalty, no penalty at all. The tradeoff: if you retire before age 62, CSRS COLA still starts immediately (unlike FERS, which delays COLA to age 62).

CSRS COLA: Full Inflation Protection from Day One

CSRS annuities receive annual Cost-of-Living Adjustments equal to the full CPI-W increase, effective every January, from the first year of retirement regardless of age.³ This is a meaningful financial advantage over FERS:

Over a 20-year retirement, this difference compounds. A $67,500 CSRS pension receiving full 2.8% COLA for 20 years reaches approximately $116,000/year. The equivalent FERS pension, receiving the capped FERS formula, would reach roughly $105,000 — about 10% less. In a high-inflation decade, the gap widens further.

CSRS Survivor Annuity Election

At retirement, you choose how much of your annuity to provide as a survivor benefit for your spouse. The survivor benefit equals 55% of the base amount you elect — from a minimum of $1/month ($22/year base) up to 55% of your full unreduced annuity.⁴

The cost to your annuity:⁴

• 2.5% of the first $3,600 of the elected base, plus
• 10% of any elected base above $3,600

Example — electing the full survivor annuity on a $67,500 pension:

• 2.5% × $3,600 = $90/year
• 10% × ($67,500 − $3,600) = 10% × $63,900 = $6,390/year
• Total annual reduction: $6,480/year (~9.6% of pension)
• Your net annuity: $67,500 − $6,480 = $61,020/year
• Survivor receives at your death: 55% × $67,500 = $37,125/year

Key distinctions from FERS survivor annuity: (1) The CSRS survivor annuity does not protect FEHB coverage — that is a separate FERS construct. Under CSRS, a surviving spouse with their own FEHB coverage or Medicare is protected regardless of election. (2) The election is irrevocable in most circumstances after retirement. (3) CSRS does not have the FERS "partial" election concept of exactly 25% — you choose any base amount from $22/year upward.

CSRS Offset: When Social Security Reduces Your Pension

CSRS Offset applies to employees who were in CSRS, left federal service, returned later, and are covered under Social Security due to the mandatory SS coverage rules enacted in 1984. These employees pay into both CSRS and Social Security simultaneously — getting the CSRS formula but also building SS credits from federal work.⁵

How the offset works: Your CSRS pension is calculated normally (full tiers). When you reach age 62 — or earlier if you are already 62 when you retire — OPM contacts SSA to determine how much of your SS benefit is attributable to federal employment. That amount is subtracted ("offset") from your CSRS annuity. You then collect the SS check directly.

The net effect: your total income (CSRS pension + SS from federal work) is roughly the same as a pure CSRS employee with no SS — but split between two payments instead of one. The offset is not a penalty; it reflects the dual contributions you made.

Social Security and CSRS: What the 2025 WEP/GPO Repeal Means

The Social Security Fairness Act (signed January 5, 2025) repealed both the Windfall Elimination Provision (WEP) and the Government Pension Offset (GPO), effective for benefits payable after December 2023.⁶ For CSRS employees, this matters in two scenarios:

1. If you have SS-covered earnings from private-sector work (prior to federal service, part-time work, or after leaving federal employment). Under WEP, your SS retirement benefit was reduced — sometimes by hundreds of dollars per month. WEP is gone. You now receive the full SS benefit your earnings record entitles you to.
2. If you are a surviving spouse or dependent of a CSRS retiree. Under GPO, spousal and survivor SS benefits were reduced by two-thirds of the government pension. A CSRS retiree's surviving spouse receiving a $2,000/month pension lost two-thirds ($1,333) from any SS spousal or survivor benefit — in many cases reducing that SS to zero. GPO is repealed. Surviving spouses of CSRS retirees now receive their full SS spousal or survivor benefit.

For retirees already receiving SS: SSA retroactively applied the repeal and issued lump-sum payments in mid-2025 covering the months from January 2024 forward. If you have not yet claimed SS from other covered employment, you should review whether claiming now makes financial sense given the full unreduced benefit.

TSP for CSRS Employees: No Match, But Still Valuable

CSRS employees can contribute to the Thrift Savings Plan, but receive no employer contribution — no automatic 1% or matching funds. Every dollar in your TSP account is money you put there yourself.⁷

Despite the lack of matching, TSP remains valuable for CSRS employees:

• Tax-deferred growth. Traditional TSP contributions reduce current-year taxable income at 7% CSRS contribution rates plus federal brackets — a meaningful shelter. A GS-13 contributing $24,500/year ($35,750 if ages 60–63) defers a significant tax bill.
• Roth TSP. Your pension is already large and inflation-indexed — a pre-tax income floor. Roth TSP contributions (after-tax now, tax-free later) hedge the risk that your pension pushes you into higher brackets in retirement. SECURE 2.0 §325 eliminated Roth TSP lifetime RMDs starting in 2024, making Roth TSP an especially useful estate vehicle.
• The G Fund. If you're nearing retirement or in retirement, the G Fund earns intermediate-term Treasury yields (~4.3% annualized in 2026) with zero principal risk — a combination not available in any IRA. Staying in TSP to keep G Fund access is often the right call for CSRS retirees.
• Rule of 55. If you separate from federal service at age 55 or later (age 50 for law enforcement/firefighter/ATC), you can withdraw from TSP without the 10% early withdrawal penalty — same as FERS employees. Rolling to an IRA before 59½ eliminates this access.

CSRS TSP allocation note. Your pension already provides substantial, inflation-indexed fixed income. This affects your optimal TSP allocation: the "bonds" role your pension fills means most CSRS employees can hold more equity in their TSP than a retiree with no pension. The L Fund glide path — designed for investors without a pension — likely underestimates the equity allocation that makes sense for CSRS employees.

CSRS Pension Estimator

Enter your service years and High-3 salary to estimate your CSRS annuity. The calculator applies the statutory tiered formula and shows the breakdown by service tier, plus an optional survivor annuity cost.

Why CSRS Employees Still Need a Financial Advisor

The pension's generosity can create a false sense of security. CSRS-specific complexity that benefits from specialist advice:

• Survivor benefit vs. FEGLI vs. private life insurance. Electing a full CSRS survivor annuity reduces your pension by ~9–10%. Private term or whole-life coverage might protect your spouse more cost-effectively — or the survivor annuity's inflation indexing might make it irreplaceable. This is an actuarial calculation, not a rule of thumb.
• WEP/GPO repeal retroactive benefits. If you or your spouse are now entitled to larger SS benefits than you were receiving, optimizing the claiming strategy — especially if one spouse is significantly older — has real dollar impact.
• CSRS Offset integration. Understanding exactly how your SS offset will work at 62, whether to delay SS to 70 (delaying doesn't change the offset), and the spousal SS implications requires careful planning.
• TSP Roth conversion window. Many CSRS employees have large traditional TSP balances and are sitting in the Roth conversion opportunity between retirement and age 63 (IRMAA base year lookback), 65 (Medicare Part B begins), or 73/75 (RMDs begin). A specialist can model the optimal conversion amount each year.
• IRMAA planning. Your CSRS pension plus TSP withdrawals plus SS plus capital gains can push a CSRS retiree into Medicare surcharge tiers. IRMAA is based on income two years prior — Roth conversions and withdrawal sequencing before 63 have multi-year tax effects.
• TSP stay vs. rollover. For CSRS retirees, the G Fund and Rule of 55 arguments to stay in TSP are often strong. But a rollover to an IRA may offer more estate flexibility and Roth conversion access. This decision is usually permanent within the context of the funds you move.