FERS Supplement Calculator

The FERS Special Retirement Supplement bridges the income gap between early federal retirement and age 62 — when Social Security eligibility begins. It's paid automatically with your FERS annuity check but is subject to an annual earnings test: if you earn too much in retirement, OPM reduces or eliminates it. Enter your numbers below to see your monthly supplement, how the earnings test affects it, and the total payout over your supplement window.

How the FERS supplement is calculated

The formula

OPM approximates the supplement as the portion of your full Social Security benefit earned during FERS service (5 U.S.C. §8421):

Monthly supplement = SS benefit at 62 × (FERS creditable years ÷ 40)

If your SS statement shows $1,400/month at age 62 and you have 30 years of FERS service: $1,400 × (30 ÷ 40) = $1,050/month. OPM rounds your FERS years up to the next full year for this calculation.

In practice, OPM uses a more detailed computation based on your actual Social Security earnings record — but the statement-based estimate is close enough for planning. If there's a meaningful difference, it's usually because your SS statement assumes continued earnings at your current rate until 62, which inflates the benefit projection if you retire early.

The 2026 earnings test

The supplement is subject to the same earnings test that applies to Social Security benefits claimed before full retirement age. For 2026, the annual limit is $24,480 — indexed to the Social Security Administration's national average wage index each year (up from $23,400 in 2025).¹

For every $2 of earned income above $24,480, OPM reduces your annual supplement by $1. At sufficiently high earnings, the supplement drops to zero.

The key timing point: OPM applies the reduction in July of the following year based on your prior-year tax return earnings. If you earn too much in 2026, the supplement reduction appears in your August 2027 annuity check — not immediately. But once the reduction kicks in, it applies for the full remaining year.

What counts as "earned income"

Only wages and net self-employment income count toward the earnings test. The following do not count:

• FERS annuity payments
• TSP withdrawals or IRA distributions
• Social Security benefits (once you start receiving them at 62)
• Investment income (dividends, capital gains, interest)
• Rental income from passive activities
• Pensions from prior employers

This distinction matters: a federal retiree who draws $50,000/year from their TSP while working part-time at $20,000/year is safely below the earnings test. Only the $20,000 W-2 income counts.

Who qualifies for the supplement

The FERS supplement is paid automatically to employees who retire on an immediate annuity before age 62:

• MRA+30 — retire at your Minimum Retirement Age (MRA, 55–57 depending on birth year) with 30+ years of service
• Age 60+20 — retire at 60 with 20+ years of service
• Age 62+5 — retire at 62; no supplement needed (SS eligibility begins at 62)
• VERA (50+20 or any age+25) — involuntary/early retirement offer; supplement starts at MRA, not necessarily at separation
• Special category (LEO/FF/ATC) — eligible at mandatory separation ages under their enhanced formula

Who does NOT get the supplement: MRA+10 employees who postpone their annuity to avoid the age penalty lose the supplement during the postponement period. FERS disability retirees do not receive it. Employees who separated with deferred retirement receive it only when their annuity begins.

The supplement vs. Social Security — two separate payments

The FERS supplement is not Social Security. It ends at age 62 regardless of when you claim Social Security — even if you defer SS to 70 to maximize your benefit. Think of it as a temporary bridge, not a replacement. Once you turn 62, the supplement stops, and you can either begin SS benefits or continue deferring for a larger permanent payment.

The math on deferring SS past 62 is compelling: delaying from 62 to 70 increases your benefit by roughly 77% (from 70% of PIA to 124% of PIA at FRA of 67). The supplement fills the gap while you wait.