CSRS Pension Calculator
The Civil Service Retirement System (CSRS) computes a federal retiree's basic annuity using a three-tier percentage on the high-3 average salary: 1.5 percent for each of the first five years, 1.75 percent for each of the next five years, and 2 percent for every year beyond ten. The accrued percentages are added and applied to the high-3 salary, with the total annuity capped at 80 percent. This calculator takes your high-3 average salary and total years of service, builds each tier, applies the 80 percent ceiling, and shows your estimated annual and monthly annuity along with the share of salary it replaces.
CSRS annuity formula
Tier 1 = 1.50% * min(years, 5)
Tier 2 = 1.75% * min(max(years - 5, 0), 5)
Tier 3 = 2.00% * max(years - 10, 0)
Accrual = Tier 1 + Tier 2 + Tier 3, capped at 80%
Annual annuity = high-3 * (accrual / 100)
The 80 percent ceiling is reached at roughly 41 years and 11 months of service. Unused sick leave can add to creditable service in the official computation but is not modelled here.
US CSRS context
- CSRS covers most federal employees first hired before 1984; later hires are generally under FERS.
- The tiered accrual rate rewards longer service with a higher percentage per year after ten years.
- The basic annuity is capped at 80 percent of the high-3 average salary.
- CSRS employees generally did not pay Social Security taxes on their federal service.
- Survivor elections and early-retirement age reductions lower the annuity from this estimate.
CSRS pension: frequently asked questions
How is the CSRS annuity calculated?
The Civil Service Retirement System uses a tiered formula on your high-3 average salary: 1.5 percent for each of the first 5 years of service, 1.75 percent for each of the next 5 years, and 2 percent for each year beyond 10. The three pieces are added and multiplied by the high-3 average salary.
What is the high-3 average salary in CSRS?
It is the highest average basic pay you earned during any three consecutive years of creditable service, normally your final three years. Enter your high-3 average as a user-editable input.
Is the CSRS annuity capped?
Yes. The CSRS basic annuity is generally capped at 80 percent of your high-3 average salary, which is reached at about 41 years and 11 months of service. This calculator applies the 80 percent cap automatically.
Does CSRS include Social Security?
Generally no. CSRS employees typically did not pay into Social Security for their federal service, so the CSRS annuity is usually the main retirement benefit. This calculator estimates only the CSRS basic annuity.
Is this my final pension amount?
It is an estimate before reductions for survivor benefits, unpaid deposits or redeposits, and any age reductions for early retirement. Your official figure comes from the Office of Personnel Management.
Official sources
- U.S. Office of Personnel Management: CSRS Information.
- U.S. Office of Personnel Management: OPM home (retirement computation).
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.