Estimate your FERS annuity benefit based on your high-three average civilian pay and years of creditable service.
Your estimated FERS annuity will appear here.
Understanding FERS Retirement Benefits
The Federal Employees Retirement System (FERS) is the primary retirement system for most federal government employees. Calculating your FERS annuity benefit involves understanding a few key components: your High-Three Average Civilian Pay, your Creditable Service, and your Age at Retirement.
Key Components of FERS Calculation
High-Three Average Civilian Pay: This is the average of your highest 36 months of basic pay earned as a federal employee. It's crucial for determining the base amount of your annuity.
Creditable Service: This refers to the total years and months you have worked in federal service and contributed to FERS, or made a deposit for previous service that is creditable.
Retirement Age: Your age when you retire significantly impacts the calculation, especially if you retire before the full retirement age.
FERS Annuity Calculation Formulas
The FERS annuity is calculated using a "benefit multiplier" applied to your High-Three Average Civilian Pay. The multiplier depends on your years of creditable service and your age at retirement.
Standard FERS Retirement (Age 62+ with 5+ Years of Service):
If you retire at age 62 or later with at least 5 years of creditable service, the formula is:
Annuity = High-Three Average Pay × 1% × Creditable Service (in years)
FERS Minimum Retirement Age (MRA) Retirement (at MRA with 10+ Years of Service):
If you retire at your Minimum Retirement Age (MRA – typically 56 years and 2 months to 57 years, depending on your birth year) with at least 10 years of creditable service, the formula is:
Annuity = High-Three Average Pay × 1% × Creditable Service (in years)
Note: This calculation gives you the "unreduced" annuity. However, most FERS retirees who take their benefit at MRA with 10+ years of service will have their annuity reduced if they haven't met the age 62 requirement. This reduction is 5% for each year they are younger than 62.
FERS Early Retirement (Age 60+ with 20+ Years of Service):
If you retire at age 60 or older with at least 20 years of creditable service, the formula is:
Annuity = High-Three Average Pay × 1% × Creditable Service (in years)
FERS Special Provisions (e.g., Law Enforcement, Firefighters):
For certain occupational groups, the rules are different. If you retire at age 50 with 20+ years of service, or after 25 years of service (regardless of age), the formula is:
Annuity = High-Three Average Pay × 1.7% × Creditable Service (in years)
Note: The calculator below uses the standard 1% multiplier for simplicity, as "special provisions" are complex and specific to job roles.
How the Calculator Works
This calculator estimates your FERS annuity based on the most common scenarios. It uses the High-Three Average Pay and Creditable Service you input. It also considers your age relative to your Minimum Retirement Age (MRA) to flag potential early retirement reductions. The calculator applies the 1% multiplier for standard retirements. For special provisions (like law enforcement or firefighter retirements), the multiplier is 1.7%, but this calculator defaults to 1% for general application. Please consult official FERS resources or your HR department for exact calculations, especially if you fall under special provisions.
Important Considerations:
This is an estimate. Your official annuity calculation will be performed by OPM (Office of Personnel Management).
FERS annuities are subject to the GPO (Government Pension Offset) and/or SSDI (Survivor Benefit Election) rules, which can affect your benefit amount or survivor benefits.
Cost-of-Living Adjustments (COLAs) are typically applied to FERS annuities each year after retirement, starting in January following the first full year of retirement.
This calculator does not account for military service buy-back, deposit for prior non-FERS service, or other complexities that might affect your creditable service or pay calculations.
function calculateFersBenefit() {
var highThreeAvgPay = parseFloat(document.getElementById("highThreeAvgPay").value);
var creditableServiceYears = parseFloat(document.getElementById("creditableServiceYears").value);
var retirementAge = parseFloat(document.getElementById("retirementAge").value);
var minimumRetirementAge = parseFloat(document.getElementById("minimumRetirementAge").value);
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = "Your estimated FERS annuity will appear here."; // Reset
// Input validation
if (isNaN(highThreeAvgPay) || highThreeAvgPay <= 0) {
resultDiv.innerHTML = "Please enter a valid High-Three Average Civilian Pay.";
return;
}
if (isNaN(creditableServiceYears) || creditableServiceYears <= 0) {
resultDiv.innerHTML = "Please enter valid Creditable Service Years.";
return;
}
if (isNaN(retirementAge) || retirementAge <= 0) {
resultDiv.innerHTML = "Please enter a valid Retirement Age.";
return;
}
if (isNaN(minimumRetirementAge) || minimumRetirementAge <= 0) {
resultDiv.innerHTML = "Please enter a valid Minimum Retirement Age (MRA).";
return;
}
var annuity = 0;
var multiplier = 0.01; // Standard multiplier for most FERS retirements
var reductionMessage = "";
// Determine the appropriate multiplier and check for reductions
if (retirementAge >= 62 && creditableServiceYears >= 5) {
// Standard retirement at age 62+ with 5+ years
annuity = highThreeAvgPay * multiplier * creditableServiceYears;
} else if (retirementAge >= minimumRetirementAge && creditableServiceYears >= 10) {
// MRA retirement with 10+ years
annuity = highThreeAvgPay * multiplier * creditableServiceYears;
// Check for reduction if retiring before 62
if (retirementAge < 62) {
var yearsUnder62 = 62 – retirementAge;
var reductionFactor = yearsUnder62 * 0.05; // 5% reduction per year under 62
var reducedAnnuity = annuity * (1 – reductionFactor);
// Ensure reduction doesn't make annuity negative, and cap it reasonably if needed
// OPM rules are complex, this is a simplified indication.
if (reducedAnnuity = 60 && creditableServiceYears >= 20) {
// Early retirement at age 60+ with 20+ years
annuity = highThreeAvgPay * multiplier * creditableServiceYears;
}
// Note: This calculator does not explicitly handle the 1.7% multiplier for special provisions.
// A full calculator would require user input for occupational series.
// Format the result
var formattedAnnuity = annuity.toLocaleString(undefined, {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2,
maximumFractionDigits: 2
});
resultDiv.innerHTML = `Estimated Annual FERS Annuity: ${formattedAnnuity}${reductionMessage}`;
}