Creditable service for federal retirement is the time OPM counts when it decides whether you can retire and how large your annuity will be. Most federal civilian employment with retirement deductions taken from your paycheck counts automatically. Military service, Peace Corps and VISTA volunteer time, temporary or non-deduction civilian work, and periods for which you once withdrew your contributions all can count too, but only if you pay the required deposit or redeposit, with interest, before you separate.
Why the Count Matters
Every year of creditable service raises your pension for life. Under FERS, each year adds 1% of your high-3 average salary to your annual annuity, or 1.1% if you retire at 62 or later with at least 20 years.1U.S. Office of Personnel Management. Computation CSRS uses a tiered formula: 1.5% per year for the first five years, 1.75% per year for the next five, and 2% per year for everything beyond ten.2U.S. Office of Personnel Management. Computation
Creditable service also decides eligibility. You cannot retire on an immediate annuity without meeting a minimum combination of age and years of service, and some categories of service that boost your annuity dollar amount don’t count toward those minimums. The distinctions below matter for both reasons.
Federal Civilian Service
Career and career-conditional appointments across the executive, legislative, and judicial branches are creditable without any action on your part, as long as retirement deductions were withheld from your pay.3Office of the Law Revision Counsel. 5 USC 8332 – Creditable Service4Office of the Law Revision Counsel. 5 USC 8411 – Creditable Service
Service without deductions is the complicated case. Under FERS, temporary or intermittent work performed before January 1, 1989, can be made creditable by paying a deposit of 1.3% of the basic pay you earned during that period, plus interest. Without the deposit, that service disappears from both your eligibility count and your annuity computation. Temporary service performed after 1988 generally cannot be credited under FERS at all, because those positions are not covered by the retirement system. A few narrow exceptions exist for certain positions abroad under the Foreign Service Act and for Peace Corps and VISTA volunteers.5U.S. Office of Personnel Management. Creditable Service
CSRS employees making deposits for non-deduction civilian service pay 7% of the basic pay earned during the service period, plus interest. The rate varied briefly in 1999 (7.25%) and 2000 (7.4%) before returning to 7% in 2001. Service performed under a different retirement system, such as the Tennessee Valley Authority or the Foreign Service, may transfer under specific conditions, and some employees hired by the District of Columbia government before certain 1980s cutoffs have transferable service as well.
Military Service
Active-duty military time can be combined with your civilian service, but only honorable service qualifies, and both retirement systems require a deposit for post-1956 service.6eCFR. 5 CFR Part 842 Subpart C – Credit for Service Interest compounds annually at Treasury-set rates. For 2026, the base rate is 4.25%.7U.S. Office of Personnel Management. Benefits Administration Letter 26-301 – Calendar Year 2026 Interest Rate
FERS: 3% Deposit
The FERS deposit is 3% of your military basic pay, plus interest that accrues from the midpoint of your military service.8U.S. Office of Personnel Management. Service Credit – Military Service The deposit must be completed before you separate from federal service. If you die without completing it, survivors can pay a lump sum before OPM finishes adjudicating a survivor annuity claim.9eCFR. 5 CFR 842.307 – Deposits for Military Service Otherwise, no deposit means no credit.
CSRS: 7% Deposit and the Catch-62 Trap
CSRS employees pay 7% of military basic pay for post-1956 service, plus interest. If you skip the deposit and later become eligible for Social Security at age 62, OPM will recalculate your annuity and strip out the military service credit entirely. This is the Catch-62 provision, and it catches people because the reduction hits years after retirement.10U.S. Office of Personnel Management. CSRS and FERS Handbook – Chapter 22 Someone who retires at 56 with four years of unpaid military credit will see the annuity drop when they turn 62, permanently. Employees who will never qualify for Social Security avoid the problem, but most people who worked outside the government at some point will eventually qualify.
Military Retired Pay
If you are already receiving military retired pay, you generally must waive it to get civilian credit for that time. Two exceptions apply: you can keep the retired pay if it is based on a combat-related disability, or if it comes from reserve component service under Chapter 1223 of Title 10.11U.S. Office of Personnel Management. Military Retired Pay The waiver has to be filed formally with your military finance center.
Peace Corps and VISTA Volunteer Service
Time as a Peace Corps volunteer, volunteer leader, or VISTA volunteer counts if you later become a federal employee under CSRS or FERS. The creditable period runs from enrollment to termination.12Office of the Law Revision Counsel. 5 USC 8332 – Creditable Service For the deposit calculation, volunteers are treated as having earned pay at the rate of the readjustment allowance they received.
The Catch-62 logic applies here too. If you qualify for Social Security at 62, OPM will exclude volunteer service from your annuity calculation unless you have paid the deposit with interest. Paying locks in the credit for good.
Refunded Service and Redeposits
If you left federal service, took a refund of your retirement contributions, and later came back, that earlier service does not automatically return with you. To restore full credit you must redeposit the refund plus interest.
Under FERS, the rule is binary: without a redeposit, the refunded service is not used to compute your annuity, and any survivor benefit shrinks accordingly. The time may still count toward the years-of-service minimums for retirement eligibility, which is a partial consolation.13U.S. Office of Personnel Management. FERS Refund Fact Sheet
CSRS depends on when the service ended. For service ending before certain 1990 or 1991 cutoffs (the exact date depends on when you separated), the service may still be credited without a full redeposit, but your monthly annuity is permanently reduced. OPM computes the reduction by dividing the unpaid balance by an actuarial factor tied to your age at retirement.14eCFR. 5 CFR 831.303 – Civilian Service For service ending after those cutoffs, an unpaid redeposit means no credit at all. Interest keeps compounding, so waiting costs money either way.
Part-Time Work, Leave Without Pay, and Sick Leave
Part-Time Service
Part-time calendar time counts in full toward the years-of-service thresholds. Twenty hours a week for a year still gives you a full year toward the 30-year MRA retirement milestone. In the annuity dollar calculation, though, OPM prorates the credit to reflect actual hours worked. That same year at half time counts as half a year of paid credit. Part-time service gets you to the retirement door on schedule; the check on the other side is proportionally smaller.
Leave Without Pay
Up to six months of leave without pay in any calendar year counts as creditable service. Anything beyond six months is deducted from your total service and can push back your eligibility date.15U.S. Office of Personnel Management. Effect of Extended Leave Without Pay (LWOP) or Other Nonpay Status on Federal Benefits and Programs LWOP for military service or while receiving workers’ compensation is excepted from that limit.
Unused Sick Leave
Accumulated sick leave is a genuine bonus. Under both CSRS and FERS, every hour of unused sick leave is added to your total service for the annuity computation, at a conversion rate of 2,087 hours per year.16U.S. Office of Personnel Management. Retirement Facts 8 – Credit for Unused Sick Leave Under the Civil Service Retirement System The important limit: sick leave only raises the dollar amount. It cannot be used to meet the minimum years-of-service requirement for retirement eligibility, and it cannot be used in the high-3 salary computation. You cannot use a sick leave balance to bridge the gap between 29 years and the 30 needed for an MRA retirement.
What to Gather and How to File
The Standard Form 50, your Notification of Personnel Action, records the dates, nature, and salary of every personnel action in your career.17U.S. Department of Commerce. Guide to Understanding Your Notification of Personnel Action Form, SF-50 Keep every one you receive. Missing SF-50s are the most common reason retirement processing stalls, and reconstructing them after the fact is slow, sometimes impossible if the originating agency no longer exists.
To apply for a service credit payment, CSRS employees use Standard Form 2803.18U.S. Office of Personnel Management. CSRS Information – Service Credit FERS employees use Standard Form 3108.19U.S. Office of Personnel Management. Standard Form 3108 – Application to Make Service Credit Payment Both forms ask you to list each period of service in chronological order with the agency name and location. Precise dates help OPM locate the corresponding payroll records and calculate what you owe.
For military credit, you also need your DD-214, the Certificate of Release or Discharge from Active Duty, which verifies your service dates and the character of your discharge. Without it, OPM cannot process a military deposit request. If you have lost your DD-214, request a replacement from the National Personnel Records Center well before you plan to retire; that process alone can take months.
Current employees submit service credit applications through their agency’s HR office, which certifies the service and forwards the package to OPM. Anyone already separated sends the forms directly to OPM’s retirement operations center.20U.S. Office of Personnel Management. Service Credit OPM then issues a billing statement showing the principal plus accumulated interest. You can pay in a lump sum or through installments, usually through the Pay.gov portal or by mailed check. Because interest keeps accruing, the money you save by paying early is often larger than people expect.