If you are a federal civilian employee hired after January 1, 1984, you are enrolled in the Federal Employees Retirement System (FERS) — one of the most comprehensive retirement programs in the United States. Yet despite decades of working under this system, many federal employees reach retirement without fully understanding how their benefits are structured or how to maximize them.

This guide covers everything you need to know.

What is FERS?

The Federal Employees Retirement System (FERS) is the retirement program for U.S. federal civilian employees. It was established by Congress in 1986 and replaced the older Civil Service Retirement System (CSRS) for employees hired on or after January 1, 1984.

FERS is built on three pillars — three separate income sources that together form your retirement income:

  1. FERS Basic Benefit (Pension) — A guaranteed, defined-benefit pension paid monthly for life.
  2. Social Security — Just like private-sector workers, FERS employees pay into and collect Social Security.
  3. Thrift Savings Plan (TSP) — A defined-contribution retirement savings account similar to a 401(k), with government matching contributions.

This three-legged structure is intentional. No single source is enough alone, but together they create a diversified, reliable retirement income.

Pillar 1: The FERS Basic Benefit (Pension)

The FERS Basic Benefit is a monthly annuity paid to you for the rest of your life after you retire. The amount is determined by a straightforward formula:

Annual Pension = High-3 Average Salary × Years of Creditable Service × Multiplier

High-3 Average Salary

Your High-3 is the average of your three consecutive highest-earning years of basic federal pay. This is typically your last three years of service, but it doesn’t have to be — it can be any three-year window during your career when your pay was highest.

Example: If you earned $88,000, $92,000, and $96,000 in your final three years, your High-3 is $92,000.

Years of Creditable Service

This is the total time you worked for the federal government, including any converted unused sick leave. Under FERS, each 174 hours of unused sick leave at retirement equals one month of additional service credit. Employees with 2,087 hours of sick leave receive a full year of credit.

The Multiplier

  • 1% for most retirees (standard rate)
  • 1.1% if you retire at age 62 or older with at least 20 years of service

That 0.1% difference might seem small, but applied over 25+ years of service, it adds up to a 10% bonus on your entire lifetime pension.

Example calculation: High-3 of $90,000, 25 years of service, retiring at age 60 (standard 1% multiplier): $90,000 × 25 × 0.01 = $22,500/year ($1,875/month)

Pillar 2: Social Security

Unlike CSRS employees, FERS employees pay into Social Security throughout their careers. This means you accumulate Social Security benefits that you can collect starting at age 62 (at a reduced rate) or at your Full Retirement Age (FRA), which is 66–67 depending on your birth year.

For federal employees who retire before 62, the FERS Annuity Supplement (also called the Special Retirement Supplement) temporarily fills the gap until Social Security begins. See our FERS Facts Reference for eligibility details.

Pillar 3: The Thrift Savings Plan (TSP)

The TSP is the federal government’s version of a 401(k). It offers:

  • Tax-deferred (Traditional) contributions — taxed when withdrawn in retirement
  • Roth contributions — taxed now, tax-free in retirement
  • Government automatic contribution — 1% of your base salary, regardless of whether you contribute
  • Government matching — up to 4% more (total of 5% government match if you contribute at least 5%)
  • 2025 contribution limit — $23,500, plus $7,500 catch-up if age 50+

The 5% agency match is essentially free money. If you don’t contribute at least 5%, you’re leaving compensation on the table.

Who is Covered by FERS?

Virtually all federal civilian employees hired after December 31, 1983 are covered by FERS. There are three tiers:

Tier Hired Employee Contribution
FERS (original) Before Jan 1, 2013 0.8% of base pay
FERS-RAE January 1–Dec 31, 2013 3.1% of base pay
FERS-FRAE After Dec 31, 2013 4.4% of base pay

All three tiers use the same pension formula — only the employee contribution rate differs.

When Can You Retire Under FERS?

Your retirement eligibility depends on your Minimum Retirement Age (MRA) and years of service:

  • MRA + 30 years — Immediate, unreduced pension
  • Age 60 + 20 years — Immediate, unreduced pension
  • Age 62 + 5 years — Immediate, unreduced pension
  • MRA + 10 years — Immediate pension, but reduced 5% for each year you are under 62

Your MRA ranges from 55 (born before 1948) to 57 (born 1970 or later). Check our FERS Facts page for the full MRA table.

Key Takeaways

  • FERS is a three-legged stool: pension + Social Security + TSP
  • Your pension = High-3 × Years of Service × 1% (or 1.1%)
  • The 1.1% multiplier at age 62+ with 20+ years adds 10% to your lifetime pension
  • TSP matching up to 5% is free money — always contribute at least 5%
  • If you retire before 62, you may be eligible for the FERS Supplement

Ready to see your numbers? Use our free FERS Calculator to estimate your pension in seconds.