FERS Special Provisions Calculator

How this is calculated

Federal law enforcement officers, firefighters, nuclear materials couriers, customs and border protection officers, members of the Capitol and Supreme Court Police, and air traffic controllers retire under rules written for people the government requires to leave early. They pay a higher share of their salary into the retirement fund, they may be forced out at 57, and in exchange the first 20 years of their service accrue at 1.7% instead of 1%. The coverage is still widely called 6c, after the CSRS subsection that created it.

The formula

1.7% × high-3 × first 20 years
+ 1% × high-3 × all service beyond 20 years

5 U.S.C. § 8415(e) sets both rates and applies them to totalservice — the statute says “so much of such individual’s total service as does not exceed 20years”, and does not ask which of it was covered. So non-covered federal service and bought-back military service sit in the same pot for the computation, even though neither counts toward the eligibility that unlocks the 1.7%rate in the first place. Service is credited in whole months on OPM’s 360-day service year, and the odd days that do not complete a month are dropped.

The enhanced rate is bought by the retirement, not by the service

This is the part that costs people the most money, and it is easy to read past. § 8415(e) does not say “service performed in a covered position accrues at 1.7%”. It says the annuity of an employee retiring under § 8412(d)(1) or (e) is computed that way. If you separate without meeting one of those two combinations, you are not retiring under those sections, and every year of covered service you performed is computed at the ordinary 1%like anyone else’s.

There is no partial credit, no vesting of the years already served, and no later event that restores the rate. An investigator who resigns at 24 years and 11 months of covered service gives up roughly a third of the annuity a colleague gets for staying one more month. That is why this calculator prints the ordinary computation next to the enhanced one on every result rather than only when the rules are unmet.

When you can go — and when you must

§ 8412(d)(1) (and § 8412(e) for controllers) pays an immediate annuity after 25 years of covered service at any age, or at age 50 with 20years of covered service. Both tests count covered service only. Unused sick leave counts toward neither — it is credited in the computation and nowhere else.

§ 8425 then makes separation mandatory: the last day of the month in which an air traffic controller turns 56, or a law enforcement officer, firefighter, nuclear materials courier or CBP officer turns 57, in each case once 20years of service are complete. An agency head may exempt an individual in the public interest — to age 60 for the officer group, and to 61for controllers. A mandatory separation is computed under the same enhanced formula, which is why § 8425 appears in § 8415(e)’s own list.

What does not apply here

No age reduction. The 5%-a-year reduction that makes an MRA+10 retirement expensive lives in § 8415(h), which reaches only retirements under § 8412(g) and § 8413(b). A special provisions annuity is paid in full at 48 the same as at 62.

No 1.1% factor. The enhanced factor for separating at 62 with 20 years excludes every covered role by name, in § 8415(i)(2). Working past 62 does not lift the second tier above 1%.

Sick leave is credited at 1%. Unused sick leave is added to total service, and because eligibility already requires at least 20 years, the 1.7% tier is always full before the sick leave arrives. It is converted by OPM’s 2,087-hour chart, a lookup rather than a division, and it never counts toward eligibility.

The survivor election is ordinary FERS. § 8419 reduces the annuity by 10% to pay a survivor 50% of it, or by 5% to pay 25%, and it is applied last.

The supplement, on better terms

A covered retiree receives the FERS annuity supplementfrom the month after separation, even at 48 — well below the minimum retirement age everyone else must reach first. The Social Security earnings test that claws the supplement back does not apply until the month after the retiree reaches that minimum retirement age, so a second career in the intervening years costs nothing. Compute it on its own page; it is a separate payment from a separate formula and it stops at 62.

What this does not model

• Whether your position is covered. Coverage is an agency determination recorded on your SF-50, not something that can be inferred from a job title. If you are unsure, the answer is in your official personnel folder, and it is worth confirming before you plan a date around it.
• The higher employee contribution covered employees pay, and the refund of excess contributions that can follow a retirement computed at the ordinary rate.
• Military service and deposits. Post-1956 military service needs a deposit to count, and non-deduction civilian service needs one too. Enter only service you know is fully creditable.
• Part-time proration and disability retirement, each computed by rules of its own.
• Transferred CSRS service. A career that began under CSRS and transferred to FERS produces a two-part annuity, with the CSRS component computed under its own formula.
• COLAs, tax, insurance and court orders.The figure shown is a starting gross annuity. FERS retirees under 62 do receive a cost-of-living adjustment on this annuity where an ordinary FERS retiree would not — a genuine advantage this tool does not project forward.

Sources

• 5 U.S.C. § 8415 — the enhanced computation (e), the age reduction and who it reaches (h), and the 1.1%factor’s exclusion of covered roles (i)(2).
• 5 U.S.C. § 8412 — eligibility: 25 years at any age, or age 50 with 20, in subsections (d) and (e).
• 5 U.S.C. § 8425 — mandatory separation at 56 and 57, and the agency exemptions.
• OPM CSRS/FERS Handbook, Chapter 46 — Special Retirement Provisions (PDF) — OPM’s own treatment of coverage, eligibility and the computation.
• OPM CSRS/FERS Handbook, Chapter 51 — Creditable Service (PDF) — the 2,087-hour sick leave conversion and its exclusion from eligibility.

Last reviewed: August 2026