FERS Disability Retirement: Eligibility, Annuity Formula, and the Age 62 Cliff

A medical condition that prevents you from doing your federal job doesn't have to mean financial freefall. FERS disability retirement provides a structured income replacement — but the formula has a sharp drop at year two and a second cliff at 62 that most people don't see coming until it's too late.

What FERS disability retirement is — and what it isn't

FERS disability retirement is an early retirement option for federal employees whose medical condition permanently prevents them from performing the essential functions of their position, and whose agency cannot reasonably accommodate the condition by reassigning them to an equivalent-pay position. It is administered by the Office of Personnel Management (OPM), not by Social Security or OWCP (workers' compensation).

It is not a Social Security disability program. It is not a workers' compensation program. And it is not a resignation — you're applying for an OPM-administered retirement benefit under 5 U.S.C. § 8451, which means you keep FEHB, you keep your TSP, and you keep your survivor annuity rights.

The practical consequence: if a GS-13 Step 5 is earning $110,000 and becomes medically unable to work, FERS disability retirement can replace roughly 60% of that in year 1 — significantly better than walking away with nothing while waiting for Social Security disability to be approved.

Eligibility requirements

To qualify for FERS disability retirement, you must meet all of the following:²

• Service: at least 18 months of creditable civilian service. This is the minimum — there is no age requirement. A 29-year-old federal employee with 18 months of service can apply.
• Medical: a documented disabling condition. The condition must prevent you from performing the essential functions of your current position (or a vacant position at the same grade and pay in the same geographic area), and it must be expected to last at least one year. OPM requires comprehensive medical documentation — diagnoses, treatment records, functional limitation statements from treating physicians, and often an agency medical review.
• Accommodation attempt: your agency must have tried first. Before OPM will approve a disability retirement, your agency must document that it considered reasonable accommodations and reassignment to a vacant position. If a reasonable accommodation exists that would let you perform the essential functions of your job, OPM will deny the application.
• SSDI filing: required by law. FERS employees must file for Social Security Disability Insurance concurrently with their OPM application. Failure to apply for SSDI can result in OPM dismissing the FERS disability application. (You don't have to receive SSDI — you have to apply.)
• Timing: apply before separation or within 1 year of separation. You can apply while still employed, or within one year after your separation date. Missing the one-year window forfeits the right to disability retirement under FERS.

How the FERS disability annuity is calculated

The disability annuity operates on a three-phase structure. Each phase uses a different formula, and the transitions between phases are where most retirees get surprised.¹

Phase 1: First 12 months

Annual annuity = 60% × high-3 average salary − 100% of monthly SSDI benefit × 12

OPM computes 60% of your high-3 and then reduces it dollar-for-dollar by the full SSDI amount. The net is your OPM check; SSDI arrives separately from Social Security. Total income from both sources equals 60% of your high-3 (assuming SSDI is approved — if not, OPM pays the full 60%).

Phase 2: Year 2 onward (until age 62)

Annual annuity = 40% × high-3 average salary − 60% of monthly SSDI benefit × 12

The formula drops to 40% of your high-3, and SSDI offsets at 60%. Your OPM check goes down; the SSDI benefit is unchanged. The total income from both sources is now less than it was in year 1.

Phase 3: At age 62 — recomputed as regular FERS

At age 62, OPM converts your disability annuity to a regular FERS annuity calculated on your actual years of service at the time of disability retirement. The formula is the standard FERS one: 1.1% × high-3 × years of service (the 1.1% multiplier applies because you're converting at age 62).

For most disability retirees, this results in a material reduction. If you went on disability at 50 with 20 years of service, at 62 you receive 1.1% × high-3 × 20 = 22% of high-3 — dramatically less than the 40% of phase 2. This age 62 cliff is the most underplanned aspect of FERS disability retirement.

Worked example: GS-13 disability retirement

Background: GS-13 Step 5, high-3 average salary of $110,000, 22 years of FERS service, medical separation at age 52. SSDI approved at $1,800/month.

At 62, OPM stops the disability offset structure entirely. The annuity becomes a fixed $2,662/month from OPM (the regular FERS formula). SSDI continues separately at $1,800/month. Combined income: $4,462 — marginally better than phase 2, because SSDI is no longer offset against the annuity at age 62. But compared to a regular retirement at 62 with 32 years of service (had the employee not become disabled), they lose 10 years of accrual.

Why this example matters for planning: the drop from year 1 ($5,500/month) to year 2 ($4,387/month) is $1,113/month. That's $13,356/year vanishing on January 1 of the second year of retirement. Many disability retirees are unprepared for this because their financial plan was built around the first-year income.

FEHB in FERS disability retirement

FEHB (Federal Employees Health Benefits) continues in FERS disability retirement under the same rules as regular retirement — you pay the employee share, OPM pays the government share, and you maintain access to the same plan options.³ The 5-year rule applies: you must have been enrolled in FEHB for the 5 years immediately before retirement (or since your earliest opportunity to enroll, if less than 5 years). FERS disability retirees are not exempt from the 5-year rule.

Medicare coordination in disability retirement has an important wrinkle: if you receive SSDI, you become eligible for Medicare Part A and Part B after 24 months of SSDI receipt — regardless of age. A 50-year-old disability retiree who has been receiving SSDI for 24 months can enroll in Medicare. At that point, the FEHB/Medicare coordination decisions described in our FEHB + Medicare guide apply, including whether to enroll in Part B and how IRMAA affects your premium based on income.

The 80% earned income rule — can you work?

Disability retirement doesn't prohibit employment — but it subjects your earnings to an annual income test. If your earned income (wages or net self-employment) in any calendar year exceeds 80% of the current pay of your former position, OPM may reduce or terminate your annuity.²

The logic: if you can earn 80% or more of what your old job currently pays, OPM considers you to have regained earning capacity, and the disability annuity may be reduced or stopped. This applies each year; the test is not a one-time determination. OPM can require you to provide income documentation annually, particularly for those under age 60.

Practical note: this rule targets earning capacity, not casual part-time work. Many disability retirees do work part-time in lower-demand roles without triggering the 80% threshold. But if you plan to start a consulting practice or transition to a demanding second career, model the income against the 80% threshold before accepting significant engagements.

What happens to your TSP

FERS disability retirement is a separation from federal service, which means your TSP vesting is determined at the time of separation and your account remains invested in your chosen funds. You can leave it in TSP, which remains a low-cost option with the institutional G Fund and other offerings. Alternatively, you can roll it over to an IRA after separation.

Early withdrawal penalty: the standard 10% IRS penalty for TSP withdrawals before age 59½ may be waived if you qualify as permanently and totally disabled under IRC § 72(m)(7). The disability must meet the IRS definition, which is similar but not identical to OPM's definition. Confirm your tax treatment with a CPA or financial advisor before making large TSP withdrawals before 59½.

FEGLI (life insurance) in disability retirement

FEGLI continues in disability retirement under the same 5-year rule as FEHB — you must have been covered for the 5 years before retirement. Basic FEGLI coverage continues at no cost during retirement; Option A, B, and C continue with age-related premium reductions applied at 65. Waiver of premium applies to Basic FEGLI if you are totally disabled when you retire and remain so — check with OPM HR or your benefits specialist for current waiver eligibility.

The OPM application process

FERS disability retirement applications are processed by OPM, not by your employing agency (though the agency initiates and forwards the paperwork). The general sequence:

1. Obtain medical documentation. Your treating physician(s) must provide comprehensive records documenting diagnosis, functional limitations, treatment attempts, and prognosis. OPM often requests additional documentation; plan for multiple rounds.
2. Agency accommodation review. HR must document that it reviewed reasonable accommodation and reassignment options. This is often a bottleneck — agencies can take weeks or months to complete this step.
3. Submit SF 3107 and SF 3112 series. These OPM forms cover your retirement application and medical documentation. You or your agency HR completes them and packages everything for OPM.
4. File SSDI concurrently. Apply at ssa.gov or your local SSA office simultaneously with your OPM application. Keep your SSDI case number and timeline handy — OPM will ask.
5. OPM review. OPM processes FERS disability applications; timelines have historically ranged from several months to over a year. You may receive an initial determination or a request for additional information.
6. Interim retirement pay. While OPM processes your application, you typically receive interim disability retirement payments — generally 60–80% of the estimated annuity. The finalized annuity is retroactive to your separation date; OPM will reconcile once the application is approved.

Denial and reconsideration: OPM denies a significant portion of initial disability retirement applications, often due to insufficient medical documentation or failure to demonstrate that the agency attempted accommodation. Applicants can request reconsideration, then appeal to the Merit Systems Protection Board (MSPB). Many federal employment attorneys and financial advisors who specialize in federal benefits assist with reconsideration and appeals.

Where an advisor fits into the plan

FERS disability retirement is rarely a one-decision event. A federal-benefits specialist can help you:

• Model the three-phase income trajectory — year 1, phase 2, and the age 62 cliff — and build a TSP withdrawal and savings strategy around the transitions. The year 1 to year 2 drop is predictable but jarring; the age 62 recalculation is often even larger.
• Survivor annuity decision — the same 50%/25% election tradeoff that regular FERS retirees face applies here. See our Survivor Annuity Calculator for the math.
• TSP withdrawal sequence — when to tap TSP vs. let it grow during the phase 2 years, particularly given the 80% earned income rule limiting work options.
• Medicare timing — at 24 months of SSDI receipt, Medicare kicks in. Coordinating FEHB with Medicare Part B in the context of your income level (IRMAA risk) requires planning that changes every year.
• OWCP transition timing — if you're currently on workers' comp and considering whether and when to convert to FERS disability, the income differential analysis depends on your age, pay rate, recovery prognosis, and tax situation.

Sources

1. OPM — FERS Disability Retirement (eligibility, annuity computation, application overview). Values verified April 2026.
2. eCFR Title 5 Part 844 — Federal Employees' Retirement System: Disability Retirement (official regulation including eligibility, accommodation requirements, and earned income test).
3. OPM — Federal Employees Health Benefits (FEHB), including continuation in retirement and the 5-year enrollment rule.
4. Social Security Administration — Disability Benefits (SSDI application, concurrent filing with OPM disability).
5. FedSmith — How to Calculate FERS Federal Disability Retirement Benefits (verification of 60%/40% formula and SSDI offset mechanics).

Annuity formulas and SSDI offset rules verified against OPM guidance and 5 CFR Part 844 as of April 2026. Annuity amounts are gross pre-tax figures; actual net amounts depend on applicable federal and state income taxes.