Five years of creditable civilian service is the line between having a future FERS pension and walking away with no annuity. Vesting is simple in concept, but its consequences are easy to underestimate.
Under FERS, vesting generally requires 5 years of creditable civilian federal service. Once vested, you have earned a future right to a FERS basic annuity, even if you leave federal service before you are old enough to retire. The pension may be deferred, reduced, or payable later, but the right exists.
Before vesting, there is no future FERS pension. You may have paid retirement deductions every paycheck, but those deductions alone do not create an annuity. The vesting rule is a cliff: 4 years and 11 months is not the same as 5 years. That makes the last few months before vesting potentially worth a lifetime stream of payments.
Employee high-3 at departure: $95,000
Leave at 4.9 years: $0 future FERS pension
Leave at 5.0 years: 95,000 x 5 x 1.0% = $4,750/year payable as a deferred annuity when eligible.
The annual number may look modest, but a lifetime pension of several thousand dollars per year can be worth tens of thousands in present value. For higher-paid employees, even a 5-year deferred pension can be material.
If you separate before completing 5 years of creditable civilian service, you generally do not qualify for a future FERS annuity. You can request a refund of your retirement contributions. That refund returns your own deductions, not the government's pension obligation and not a replacement for a lifetime annuity.
The refund decision deserves care. Taking a refund can eliminate future annuity rights connected to that service unless you later return to federal employment and make any required redeposit under rules then in effect. If you might return to federal service, talk to HR before requesting a refund. A short-term cash refund can become expensive if it disrupts future service credit.
After 5 years, leaving federal service no longer means losing every pension dollar. If you separate before retirement age and leave your FERS contributions in the system, you may later claim a deferred annuity. The amount is based on your high-3 and years of service at separation, not your salary at the date you eventually claim.
This distinction matters. A deferred pension usually does not grow with federal pay raises after you leave. If you leave at age 40 with a $100,000 high-3 and 8 years of service, the formula is based on those numbers. When you claim years later, the pension is not recalculated as if your federal salary had continued to rise.
| Departure | Future right | Key limitation |
|---|---|---|
| Under 5 years | No pension | Refund only, generally |
| 5+ years | Deferred annuity | Based on pay/YOS at departure |
| MRA+10 | Immediate or postponed annuity | Possible 5%/yr reduction |
| Immediate retirement | Immediate annuity | May preserve FEHB if rules met |
Deferred retirement can be valuable, but it is not the same as retiring from federal service on an immediate annuity. Healthcare and supplement rules are different.
When you leave federal service, you may be tempted to request a refund of FERS retirement deductions. The money is yours, but taking it can erase credit for that service for annuity purposes unless restored later. If you return to federal service, you may need to redeposit refunded amounts, possibly with interest, to make the prior service count again.
The best decision depends on whether you expect to return. If you are certain you will never work for the federal government again and are not vested, a refund may be reasonable. If you are vested, leaving contributions in place can preserve your deferred annuity. If there is any realistic chance of returning, keeping the service credit intact may be worth more than the short-term refund.
This is one area where official guidance matters. Your agency HR office and OPM forms can explain the current refund and redeposit rules for your exact situation.
FERS pension vesting is separate from TSP ownership. Your own TSP contributions and their earnings are always yours. Agency matching contributions are generally yours once deposited, while the automatic 1% agency contribution has its own vesting rules for some employees. Do not assume pension vesting and TSP vesting are identical.
FEHB is even more different. Being vested in FERS does not let you keep federal health insurance in retirement if you leave before immediate retirement eligibility. Deferred retirees generally cannot carry FEHB into retirement. To keep FEHB as a retiree, you usually need to retire on an immediate annuity and satisfy the 5-year FEHB enrollment requirement.
Employee leaves at age 45 with 12 years of service. They are vested and can claim a deferred pension later. But because they did not retire on an immediate annuity, they generally do not keep FEHB into retirement.
This is why the break-even cost of leaving federal service can be much higher than the pension alone. A vested deferred pension may remain, but FEHB subsidy, annuity supplement, future TSP match, and future high-3 growth may be lost.
The break-even calculator estimates pension and FEHB value at risk.