Federal Retirement Calculator (FERS)
Estimate a FERS basic annuity using your high-3 average pay, creditable service and retirement age. The calculator applies the general FERS 1%/1.1% computation and includes a separate special-provision mode for covered law enforcement officers, firefighters and air traffic controllers.
High-3 × Years × MultiplierStep-by-step proof
- Enter your High-3 salary, years of service, and age above to see the calculation unfold step by step.
Estimate the basic FERS annuity computation
Use this page to test the basic annuity math with your own planning inputs. Eligibility and the final payable annuity depend on your actual federal service record and the retirement provision that applies to you.
For most non-disability FERS retirements, OPM computes the basic annuity from your high-3 average pay, your creditable service used in the computation, and an applicable percentage. OPM states that the general percentage is 1% for most cases and 1.1% when a person separates for retirement at age 62 or older with at least 20 years of service.
Your high-3 is not necessarily your final salary. OPM defines it as the highest average basic pay earned during any three consecutive years of service. Those years are often the final three, but an earlier period can be used when basic pay was higher then.
The special-provision calculation is separate. For employees eligible for the special FERS formula, OPM uses 1.7% of high-3 pay for the first 20 years of covered law-enforcement, firefighter or air-traffic-controller service, plus 1% for additional creditable service. This calculator reproduces that arithmetic but does not decide whether your position or service qualifies for the special provision.
How this FERS calculator computes your basic annuity
This calculator applies the standard FERS basic annuity formula published by OPM: multiply your High-3 salary by your years of service and by the multiplier that matches your age and job category.
The FERS calculator formula
Annual Pension = High-3 Salary × Years of Service × Multiplier. The multiplier is 1% for most employees, or 1.1% if you retire at age 62 or older with at least 20 years of service.
What counts as High-3
OPM defines your high-3 as your highest average basic pay earned during any 3 consecutive years of service. It is often your final 3 years, but can be an earlier period. Overtime and bonuses are not included in basic pay for this purpose.
Special provision employees
For employees eligible for the special formula, OPM uses 1.7% for the first 20 years of covered law-enforcement, firefighter or air-traffic-controller service, plus 1% for additional creditable service. Eligibility for the special provision is a separate determination.
What this doesn’t include
The FERS Special Retirement Supplement, Social Security, TSP withdrawals, survivor benefit reductions, and the MRA+10 reduced annuity all affect your real payout but aren’t modeled in this basic annuity estimate.
Three basic-annuity calculation examples
These are illustrative inputs, not real personnel records. They demonstrate only the computation modeled by this calculator.
General FERS: age 62, 25 years
General FERS: age 60, 25 years
Special provision: 22 years
Where FERS pension estimates go wrong
Using your final salary instead of your High-3
Your final salary and your High-3 average are often close but rarely identical. A late-career demotion, reduced hours, or a pay-capped position can pull your High-3 below your last drawn salary, lowering the estimated annuity.
Assuming the 1.1% multiplier always applies at 62
The higher 1.1% multiplier requires both conditions — age 62 or older and at least 20 years of creditable service. Retiring at 62 with only 15 years still uses the standard 1% rate.
Applying 1.7% to all years for special provision employees
The 1.7% rate applies to the first 20 years of covered special-provision service. Additional creditable service is computed at 1%, not 1.7%.
Forgetting the MRA+10 reduction
Under MRA+10, OPM generally reduces the annuity by 5/12 of 1% for each full month the annuity begins before age 62. The reduction can be reduced or eliminated by postponing the annuity, and OPM lists exceptions including at least 20 years of service with the annuity beginning at age 60 or later. This calculator does not model those rules.
Treating this as your full retirement income
The FERS basic annuity is one leg of a three-part retirement system that also includes Social Security and the Thrift Savings Plan. Estimating your total retirement income from this figure alone understates what you’ll actually receive.
FERS calculator: frequently asked questions
What is the FERS basic annuity formula?+
How is my High-3 average salary calculated?+
Who qualifies for the special provision (1.7%) multiplier?+
Does this calculator include the FERS Special Retirement Supplement?+
What if I retire early under MRA+10?+
Does this calculator work for CSRS employees?+
Is this an official OPM annuity estimate?+
Other tools for federal employees planning ahead
These related payroll and debt-planning tools can help with broader budgeting alongside a separate FERS annuity estimate.
Formula references
- FERS Information: Computation. U.S. Office of Personnel Management (OPM.gov).
- FERS Information. U.S. Office of Personnel Management (OPM.gov).
- FERS Information: Eligibility. U.S. Office of Personnel Management (OPM.gov).
- FERS Information: Types of Retirement. U.S. Office of Personnel Management (OPM.gov).
- CSRS and FERS Handbook, Chapter 54. U.S. Office of Personnel Management.
- CalcsDone Methodology