Creditable Service: Eligibility, Deposits, and Sick Leave

Creditable service for federal retirement is the total length of qualifying federal employment that OPM uses to decide whether you can retire and how much your monthly annuity will be. Under FERS, you need at least five years of creditable civilian service just to vest, and every additional year, month, and day feeds directly into the pension formula. The category is broader than the time shown on your current SF-50: it can include military duty, part-time work, certain volunteer service, limited periods of leave without pay, and unused sick leave at retirement, though some of those only count if you pay a deposit into the retirement fund.

How Creditable Service Sets Your Annuity

Your creditable service is one of the two numbers that determine your pension. The other is your high-3, the highest average basic pay you earned during any three consecutive years of service, with each rate weighted by how long you received it.

Under FERS, the basic benefit equals a percentage of the high-3 multiplied by your total years and months of creditable service. The multiplier is 1 percent per year in most cases. It rises to 1.1 percent per year if you retire at age 62 or later with at least 20 years of service.¹ Over a 25-year career with a high-3 of $100,000, that difference works out to roughly an extra $2,500 per year for life.

CSRS uses a tiered formula: 1.5 percent of the high-3 for the first five years, 1.75 percent for the next five, and 2 percent for every year beyond ten.² A CSRS employee with 30 years of service receives about 56.25 percent of the high-3.

How Creditable Service Sets Your Eligibility

Service years also decide whether you can draw an immediate pension at all. FERS offers four combinations of age and service:³

Age 62 with 5 years of creditable civilian service, the baseline for any FERS retirement.
Age 60 with 20 years, full annuity at the 1 percent multiplier.
Minimum Retirement Age with 30 years, full annuity.
MRA with 10 years, an immediate but reduced annuity — 5 percent less for each year you are under age 62.

Your MRA depends on your year of birth. Anyone born in 1970 or later has an MRA of 57. Earlier birth years fall somewhere between 55 and 57, stepping up in two-month increments.³

If you leave federal service before qualifying for any immediate benefit, five years of creditable civilian service still gets you a deferred annuity starting the first day of the month after you turn 62, provided you don’t take a refund of your retirement contributions when you go.⁴ Taking the refund destroys the deferred benefit entirely.

What Kinds of Federal Work Count

Federal law defines creditable service in 5 U.S.C. § 8411 for FERS and 5 U.S.C. § 8332 for CSRS. Both statutes list categories of service that count and then attach deposit requirements to periods where retirement deductions weren’t withheld from your pay.⁵

Covered Civilian Service

Covered service is the simplest category. You worked in a position where retirement deductions came out of every paycheck, and that time counts automatically toward both eligibility and computation. No deposit, no paperwork beyond the normal personnel record.

Non-Covered Civilian Service

Non-covered service is federal work where no retirement deductions were withheld — temporary appointments, certain intermittent positions, and jobs in agencies outside the standard retirement system. For FERS employees, non-covered civilian service performed before January 1, 1989 can be made creditable by paying a deposit of 1.3 percent of basic pay for those periods, plus interest.⁶ Non-covered civilian service performed on or after January 1, 1989 generally cannot be credited at all.⁷ The cutoff catches people who held temporary federal jobs in the early 1990s and assumed the time would count.

Military Service

Honorable active-duty military service is creditable under both systems, but only if you pay a deposit. For post-1956 military service under FERS, the deposit is 3 percent of your basic military pay plus interest. Under CSRS it’s 7 percent.⁶ Skip the deposit and OPM cannot credit the military time at all; it drops out of the annuity computation as if it never happened. If you’re relying on those years to hit an eligibility threshold like 20 years for the age-60 path, the deposit has to be paid in full before you retire, or you may not qualify to retire when you planned.

Time as a cadet or midshipman at a military academy can also be credited on the civilian side with a deposit, and no waiver of active-duty retired pay is required because academy time isn’t included in military retired pay.⁸

Peace Corps and VISTA Volunteer Service

FERS employees can credit Peace Corps or VISTA volunteer service performed on or after January 1, 1989 by paying a deposit of 3 percent of earnings during the volunteer period. Interest accrues after a two-year grace period from the date you first entered federal employment.⁹ A VISTA volunteer who took an educational award instead of a stipend still owes a deposit calculated on the stipend they would have received. Training periods before actual enrollment don’t count.

Part-Time Service

Part-time years count fully for eligibility. Ten years of half-time work still gets you ten years toward the age-and-service thresholds. Computation is a different story. FERS applies a proration factor equal to the ratio of your actual hours worked to a full-time schedule, so a year at 20 hours per week in a 40-hour position contributes a factor of 0.5 to that year’s annuity value.¹ Your career proration factor blends every full-time and part-time period across your service.

Leave Without Pay and Furloughs

Not every day away from the office is a gap in your record. OPM allows up to six months of nonpay status per calendar year to count as creditable service. Anything beyond that six-month threshold within a single calendar year is not creditable and pushes back the date you reach your service milestones.¹⁰ Administrative furloughs follow the same nonpay rules. Retirement coverage continues at no cost to you during nonpay status, and nonpay periods falling inside your high-3 window are included at the rate of basic pay that was in effect at the time.

Military leave without pay is handled separately. Under USERRA, the full period of absence for military service must be treated as continuous employment for pension purposes. Employer pension contributions resume when the employee returns, and the employee may make up missed contributions over a period of up to three times the length of military service, capped at five years.¹¹

Unused Sick Leave at Retirement

Sick leave you accumulated and never used gets added to your service total when you retire, but only for computing the annuity amount. It cannot help you meet an age or service eligibility requirement. By law, 2,087 hours of sick leave equals one year of additional service credit.¹² FERS employees separating on or after January 1, 2014 receive credit for 100 percent of their sick leave balance; CSRS employees have always received full credit.¹³

A balance of 1,500 hours works out to roughly eight and a half months of extra service. Run that through the annuity formula against a high-3 near $95,000 and it adds real money to every check for the rest of your life.

Buying Back Prior Service

Several categories of service only become creditable if you pay a deposit into the retirement fund. This is commonly called “buying back” time, and the cost climbs with interest the longer you wait.

Military Deposits

Post-1956 military service under FERS costs 3 percent of your basic military pay plus compounding interest.⁶ CSRS deposits are 7 percent. The calendar year 2026 interest rate is 4.25 percent, though the rate actually applied to your account is a composite of the rates in effect during the twelve months before your interest accrual date.¹⁴ Someone who delays a military buyback for 15 years can easily see the interest exceed the original deposit. The deposit must be paid to your employing agency before you separate; if you’re within six months of retirement, OPM recommends filing the deposit request with your retirement application.

Pre-1989 Civilian Deposits

FERS employees who had non-covered civilian service before 1989 pay 1.3 percent of basic pay for those periods, plus interest that starts accruing two years after the date you were first employed under FERS in a covered position.⁶

Redeposits

If you previously left federal service and took a refund of your retirement contributions, you can restore that lost service credit by redepositing the refunded amount plus interest. FERS employees who took a FERS refund and were covered by FERS again on or after October 28, 2009 may make a redeposit.⁷ Skipping the redeposit permanently reduces your monthly annuity, so this is worth addressing early in a return to federal service before interest makes it prohibitive.

How OPM Totals the Time

OPM adds up all your creditable periods in years, months, and days. Twelve months make a year, and any leftover fractional part of a month is dropped from the total. A separation from federal service of more than three calendar days creates a break in service that itself is not creditable.⁵ Two weeks between jobs means fourteen days you don’t get back.

Verifying Your Record Before You Retire

Every appointment and separation in your career leaves a paper trail, and confirming your creditable service means pulling those records together well in advance. At a minimum, you need your Social Security number and the exact start and end dates of every federal position. Military veterans need the DD Form 214 documenting total creditable military service.¹⁵ The names of employing agencies and geographic work locations help OPM find older personnel folders.

The formal application to pay for service credit is Standard Form 3108 for FERS employees or Standard Form 2803 for CSRS employees.¹⁶ Both forms require your service history in chronological order with correct department codes and appointment dates, and errors cause delays, so cross-check the entries against your SF-50s and military records before submitting. Starting the verification process a year or more before your planned retirement date leaves time to track down missing records and pay any outstanding deposits before interest compounds further.

One boundary worth naming: a court order from a divorce, legal separation, or annulment can divide your annuity with a former spouse, but doing so doesn’t add or subtract creditable service. It reassigns a share of the annuity your creditable service produces. The rules for those orders live in 5 CFR Part 838 and are separate from the service-credit rules covered here.¹⁷

1
U.S. Office of Personnel Management. FERS Information – Computation
2
U.S. Office of Personnel Management. CSRS Information – Computation
3
U.S. Office of Personnel Management. FERS Information – Eligibility
4
U.S. Office of Personnel Management. FERS Information – Types of Retirement
5
Office of the Law Revision Counsel. 5 USC 8411 – Creditable Service
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U.S. Office of Personnel Management. FERS Information – Service Credit
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U.S. Office of Personnel Management. FERS Information – Creditable Service
8
Defense Civilian Personnel Advisory Service. 2024 Symposium – Military Deposit
9
U.S. Office of Personnel Management. Crediting Peace Corps/VISTA Service
10
U.S. Office of Personnel Management. Effect of Extended Leave Without Pay (LWOP) (or Other Nonpay Status) on Federal Benefits and Programs
11
U.S. Department of Labor. VETS USERRA Fact Sheet 1 – Frequently Asked Questions
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U.S. Geological Survey. Sick Leave Conversion Chart
13
U.S. Office of Personnel Management. Retire FAQ – Will I Get Paid for Unused Sick Leave in Retirement
14
U.S. Office of Personnel Management. Benefits Administration Letter 26-301 – Calendar Year 2026 Interest Rate
15
National Archives. DD Form 214 – Discharge Papers and Separation Documents
16
U.S. Office of Personnel Management. SF 3108 – Application to Make Service Credit Payment
17
eCFR. Court Orders Affecting Retirement Benefits – 5 CFR Part 838