Retirement Planning / Federal Benefits

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.

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Created by Umer Farooq, Founder & Developer of CalcsDone
Method based on published U.S. Office of Personnel Management (OPM) guidance Last updated:
High-3 × Yrs × Mult.
The full FERS basic annuity formula
1% or 1.1%
Standard multiplier; 1.1% at 62+ with 20+ years
1.7%
Special-provision computation rate, up to 20 yrs
3 years
Highest average basic pay during any 3 consecutive years
Enter Values
FERS calculator formula: High-3 × Years × Multiplier
$
yrs
yrs
Quick years of service
Quick retirement age
Estimated Annual Pension
$0.00
Estimated Monthly Pension
$0.00
Multiplier Used
1.0%
Calculation Breakdown
Enter your details above

Step-by-step proof

  1. Enter your High-3 salary, years of service, and age above to see the calculation unfold step by step.
Unofficial planning estimate only. This tool estimates only the basic annuity computation from the values you enter. It does not determine retirement eligibility and does not model every rule that can change an actual benefit, including MRA+10 or postponed/deferred retirement, survivor elections, deposits or redeposits, part-time service, unused sick leave, a CSRS component, disability retirement, court orders, the retiree annuity supplement, Social Security, TSP withdrawals, taxes, or other individual circumstances. Special-provision mode is a computation aid only; selecting it does not establish that your position or service qualifies. For an official estimate, use your agency’s records and contact your agency HR office or OPM. See OPM’s FERS computation guidance.
What this calculator does

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 covered air traffic controllers, firefighters and law enforcement officers, OPM’s computation page uses 1.7% for qualifying service up to 20 years and 1% for service exceeding 20 years. This calculator reproduces that arithmetic but does not decide whether your position or service qualifies for the special provision.

How it works

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 covered law enforcement officers, firefighters and air traffic controllers, OPM uses 1.7% for qualifying service up to 20 years, plus 1% for service exceeding 20 years. 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.

Worked examples

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

High-3$95,000
Service25 years
Percentage1.1%
$26,125 / year
$95,000 × 25 × 1.1% = $26,125, or about $2,177.08 per month before any applicable reductions or other adjustments.

General FERS: age 60, 25 years

High-3$95,000
Service25 years
Percentage1.0%
$23,750 / year
$95,000 × 25 × 1% = $23,750. This example shows the formula only; it does not determine whether the person is eligible for an immediate unreduced annuity.

Special provision: 22 years

High-3$88,000
First 20 years1.7%
Additional 2 years1.0%
$31,680 / year
$88,000 × 20 × 1.7% = $29,920; plus $88,000 × 2 × 1% = $1,760. Total: $31,680.
Common mistakes & edge cases

Where FERS pension estimates go wrong

1

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.

2

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.

3

Applying 1.7% to all years for special provision employees

The 1.7% rate for law enforcement officers, firefighters, and air traffic controllers only applies to the first 20 years of service. Additional years beyond that use the standard 1% multiplier, not 1.7%.

4

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.

5

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.

FAQ

FERS calculator: frequently asked questions

What is the FERS basic annuity formula?+
The FERS basic annuity is calculated as High-3 average salary multiplied by years of creditable service multiplied by a 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. This federal FERS retirement calculator applies that exact formula.
How is my High-3 average salary calculated?+
Your High-3 is the average of your highest 36 consecutive months of basic pay over your entire federal career, not just your final salary. It generally excludes bonuses, overtime, and most special pay beyond base pay.
Who qualifies for the special provision (1.7%) multiplier?+
Law enforcement officers, firefighters, and air traffic controllers covered under FERS special provisions use a 1.7% multiplier for their first 20 years of creditable service, with additional years calculated at the standard 1% rate. This FERS pension calculator applies that split automatically when you select the special provision category.
Does this calculator include the FERS Special Retirement Supplement?+
No. The Special Retirement Supplement is a separate benefit paid to some FERS employees who retire before age 62, bridging the gap until Social Security eligibility. It’s calculated differently and isn’t included in the basic annuity estimate above.
What if I retire early under MRA+10?+
OPM generally applies a reduction of 5/12 of 1% for each full month an MRA+10 annuity begins before age 62. Postponing the annuity can reduce or eliminate the reduction, and exceptions can apply. This calculator does not determine or apply MRA+10 eligibility or reductions.
Does this calculator work for CSRS employees?+
No — this tool covers the FERS basic annuity formula only. CSRS uses a different tiered formula based on High-3 salary and years of service, and most federal employees hired since 1987 fall under FERS rather than CSRS.
Is this an official OPM annuity estimate?+
No. This federal FERS calculator is an unofficial planning tool for educational purposes. For a binding, official annuity estimate, contact your agency’s HR office or the U.S. Office of Personnel Management directly.
Which calculator do you need?

Other tools for federal employees planning ahead

FERS is currently the only retirement calculator in this category, so these are the closest payroll and financial-planning tools on calcsdone for federal employees mapping out take-home pay and debt before retirement.

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Umer Farooq

Founder & Developer, CalcsDone

Umer Farooq founded CalcsDone and develops its calculator pages. For this calculator, the computation method and explanatory notes reference published guidance from the U.S. Office of Personnel Management (OPM). CalcsDone is independent of OPM and is not a U.S. government website.

This page was updated on September 20, 2026. If you notice an unclear explanation, broken function, or source that should be reviewed, you can report it through the contact page.

OPM guidance cited below No account or sign-up required No account required to calculate Updated September 20, 2026
Sources & methodology

Formula references

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