FERS vs CSRS: Federal Retirement Systems Compared
The two federal retirement systems work very differently. This guide breaks down the pension formulas, COLAs, TSP rules, and survivor benefits so you can understand exactly what your system provides.
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CSRS and FERS at a Glance
CSRS (Civil Service Retirement System) was created in 1920 and closed to new hires on January 1, 1987. It provides a single, generous defined-benefit pension. CSRS employees do not participate in Social Security and receive no TSP agency matching.
FERS (Federal Employees Retirement System) replaced CSRS in 1987. It uses a three-part structure: a smaller pension, full Social Security coverage, and TSP with 5% agency matching. About 98% of the current federal workforce is under FERS.
~44,000
Active CSRS employees remaining (FY2022)
98.4%
Federal workforce under FERS
1.5M+
CSRS annuitants still receiving benefits
Side-by-Side Comparison
| Feature | CSRS | FERS |
|---|---|---|
| System type | Defined benefit only | Three-legged stool |
| Created | 1920 | 1987 |
| Pension multiplier | 1.5% / 1.75% / 2% (tiered) | 1% (1.1% at age 62 with 20+ yrs) |
| 30-year pension | 56.25% of high-3 | 30% of high-3 (33% at 62) |
| Pension cap | 80% of high-3 | No cap |
| Employee contribution | 7% | 0.8% - 4.4% |
| Social Security | No | Yes (full coverage) |
| TSP match | No match (can contribute) | 5% total (1% auto + 4% match) |
| COLA | Full CPI-W, no cap | Capped (CPI-1% if CPI > 3%) |
| COLA starts | Immediately at retirement | Age 62 (exceptions for special categories) |
| Max survivor benefit | 55% of annuity | 50% of annuity |
| Retirement supplement | N/A | Yes (bridges to SS at 62) |
| Sick leave credit | 100% (always) | 100% (since 2014) |
| Disability retirement | 5 years service required | 18 months service required |
Pension Formulas with Dollar Examples
CSRS Formula (Tiered)
First 5 years:1.5% per year
Years 6-10:1.75% per year
Years 11+:2.0% per year
Cap:80% of high-3
FERS Formula (Flat)
Standard:1.0% x high-3 x years
Bonus (age 62+, 20+ yrs):1.1% x high-3 x years
Cap:None
Pension by Years of Service ($100,000 High-3)
| Years | CSRS Pension | FERS Pension (1%) | FERS Pension (1.1%) |
|---|---|---|---|
| 10 | $16,250 | $10,000 | $11,000 |
| 20 | $36,250 | $20,000 | $22,000 |
| 25 | $46,250 | $25,000 | $27,500 |
| 30 | $56,250 | $30,000 | $33,000 |
| 35 | $66,250 | $35,000 | $38,500 |
| 40 | $76,250 | $40,000 | $44,000 |
Remember: FERS pension is only one piece of the puzzle. Add Social Security (~$25,000-35,000/year for most federal retirees) and TSP withdrawals to get total retirement income. Use the FERS Retirement Calculator to model your complete picture.
Retirement Eligibility
CSRS Eligibility
| Type | Age | Service |
|---|---|---|
| Voluntary | 62 | 5 years |
| Voluntary | 60 | 20 years |
| Voluntary | 55 | 30 years |
| Early (VERA) | 50 / Any | 20 / 25 years |
FERS Eligibility
| Type | Age | Service | Notes |
|---|---|---|---|
| Immediate | 62 | 5 years | No reduction |
| Immediate | 60 | 20 years | No reduction |
| Immediate | MRA | 30 years | No reduction |
| Reduced | MRA | 10 years | 5% per year under 62 |
| Early (VERA) | 50 / Any | 20 / 25 years | No reduction |
| Deferred | 62 | 5 years | No reduction |
FERS Minimum Retirement Age (MRA)
Your MRA depends on your birth year: 55 (born before 1948), 56 (1953-1964), or 57 (1970+), with gradual increases in between. See the FERS Retirement Guide for the full MRA chart.
Cost-of-Living Adjustments (COLA)
This is one of the biggest differences between the two systems. CSRS retirees get full inflation protection from day one. FERS retirees get a reduced COLA that does not start until age 62.
| Feature | CSRS | FERS |
|---|---|---|
| Formula | Full CPI-W | Full CPI if ≤ 2%; capped at 2% if CPI 2-3%; CPI minus 1% if CPI > 3% |
| When it starts | Immediately at retirement | Age 62 (most retirees) |
| 2026 COLA | 2.8% | 2.0% (capped) |
Why this matters: A CSRS retiree who retired at 55 gets COLA protection for 7 years before a FERS retiree at the same age starts receiving any adjustments. During high-inflation periods, this difference compounds significantly.
Survivor Benefits
| Feature | CSRS | FERS |
|---|---|---|
| Maximum benefit | 55% of annuity | 50% of annuity |
| Cost to retiree | ~2.5% of first $3,600 + 10% above | 10% flat reduction |
| Partial option | Flexible base amount | 25% option (5% reduction) |
| Spousal consent | Required to waive | Required to waive |
CSRS Offset Explained
CSRS Offset is a hybrid version created in 1987 for employees who had 5+ years of CSRS service before 1987, left government for more than a year, and returned. It works like regular CSRS with one critical difference.
The Age 62 Offset
At age 62, your CSRS annuity is automatically reduced by the Social Security benefit earned during your Offset service period. This happens even if you do not claim Social Security at 62. The reduction only applies to the SS benefit attributable to Offset service, not your total SS earnings.
The Social Security Fairness Act (signed January 5, 2025) repealed WEP and GPO, which means CSRS Offset retirees may now receive full Social Security benefits from non-Offset employment. This is a significant improvement for Offset employees with private-sector work history. Read more in our Social Security Fairness Act guide.
Which System Is Better? It Depends.
Short Career (10-15 years): FERS Wins
FERS provides Social Security portability and TSP matching. If you leave government mid-career, your TSP balance transfers to a 401(k) or IRA. CSRS only offers a refund of contributions with 3% interest or a deferred annuity at 62 based on your salary at separation (not inflation-adjusted).
Full Career (30+ years): CSRS for Guaranteed Income
CSRS at 30 years: $56,250/year pension on a $100K salary. FERS at 30 years: $30,000 pension + ~$30,000 Social Security + TSP withdrawals from a $1M+ balance. CSRS provides more guaranteed income. FERS can match or exceed it, but your TSP balance carries market risk.
Early Retirement (55-57): Depends on COLA Needs
CSRS retirees at 55 get full COLA immediately. FERS retirees get the FERS Supplement to bridge to Social Security at 62, but no COLA until 62. In high-inflation environments, CSRS early retirees are better protected.
Leaving Government Mid-Career: FERS Wins
FERS employees keep their full Social Security credits and can roll their TSP into any 401(k) or IRA. CSRS employees who leave mid-career face a deferred annuity calculated on their pay at separation, which erodes significantly over 20+ years of inflation before they can collect at age 62.
The 1998 Transfer Window
The last opportunity to switch from CSRS to FERS was the 1998 open season (July 1 through December 31, 1998). The decision was irrevocable. Roughly 1 million CSRS employees had the opportunity.
Most employees with 15+ years of service in 1998 were advised to stay in CSRS because the higher pension multiplier outweighed TSP matching and Social Security. Younger employees with shorter service histories generally benefited from switching.
There is no current provision to transfer, and no legislation is pending to open a new window. Earlier open seasons occurred in 1987 (when FERS was created) and 1998. Both are permanently closed.
2026 Specifics
TSP Contribution Limits
| Regular contributions | $24,500 |
| Catch-up (age 50+) | + $8,000 |
| Super catch-up (ages 60-63) | + $11,250 |
Both CSRS and FERS employees share the same TSP limits. The difference: FERS gets 5% agency matching, CSRS gets none. See the TSP Guide 2026 for fund details and strategies.
FERS Employee Contribution Rates
| Hired before 2013 | 0.8% |
| Hired in 2013 (FERS-RAE) | 3.1% |
| Hired 2014+ (FERS-FRAE) | 4.4% |
Pending Legislation (Not Yet Enacted)
A House committee has proposed increasing all FERS contribution rates to 4.4% and eliminating the FERS Special Retirement Supplement for new retirees effective January 2028. Neither provision has been enacted as of February 2026. Current rates remain unchanged.
Frequently Asked Questions
Can I switch from CSRS to FERS in 2026?↓
No. The last opportunity to transfer from CSRS to FERS was the 1998 open season (July-December 1998). That election was irrevocable, and no new transfer windows have been created. There is no pending legislation to reopen transfers.
Which system provides a better retirement at 30 years of service?↓
It depends on what you value. CSRS provides a guaranteed pension of 56.25% of your high-3 salary. FERS provides a 30% pension plus Social Security (~$25,000-35,000/year) plus your TSP balance (potentially $1M+ with consistent investing). CSRS offers more guaranteed income. FERS potentially offers higher total income but requires investment discipline.
Do CSRS employees get Social Security?↓
CSRS employees do not pay Social Security tax and do not earn credits for their federal service. However, they may qualify through other employment. The Social Security Fairness Act (signed January 5, 2025) repealed WEP and GPO, so CSRS retirees with outside Social Security credits now receive their full benefit.
What is CSRS Offset and how does it affect my pension?↓
CSRS Offset applies to employees who had 5+ years of CSRS service before 1987, left government for more than 1 year, and returned. Your pension uses the same CSRS formula, but at age 62 it is automatically reduced by the Social Security benefit earned during your Offset service period, even if you do not claim Social Security at 62.
Does the FERS 1.1% multiplier apply to all my years?↓
Yes. If you retire at age 62 or later with at least 20 years of service, your entire pension is calculated at 1.1% instead of 1.0%. This applies to all years of creditable service, not just years worked after 62. For example, 30 years at 1.1% = 33% of high-3 instead of 30%.
Can CSRS employees contribute to the TSP?↓
Yes, but there is a critical difference: CSRS employees receive no agency matching contributions. FERS employees receive a 1% automatic agency contribution plus up to 4% matching (5% total). Both systems are subject to the same annual limits ($24,500 in 2026; $32,500 with catch-up for age 50+).
How do CSRS and FERS COLAs differ?↓
CSRS retirees receive the full CPI-W adjustment with no cap, starting immediately at retirement. FERS retirees receive a capped COLA (CPI minus 1% if CPI exceeds 3%) that does not begin until age 62 for most retirees. In 2026, CSRS received 2.8% while FERS received 2.0%.
Is my CSRS or FERS pension taxable?↓
Yes, both are subject to federal income tax. The portion representing your own after-tax contributions is returned tax-free using the IRS Simplified Method (Publication 721). State tax varies: 9 states have no income tax, and some additional states exclude federal pensions.
Related Calculators & Guides
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TSP Guide 2026
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FERS Supplement Guide
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