FEHB and Medicare at 65: Should You Take Part B?
If you carry FEHB into retirement, you keep it for life — Medicare doesn't replace it. But at 65 you become eligible for Medicare, and that raises a genuine decision: do you also enroll in Medicare Part B, which has its own monthly premium, or keep FEHB alone? There's no single right answer, but there is a wrong way to decide — by accident, after a deadline has passed.
The two parts of Medicare that matter here
- Part A (hospital). Premium-free for nearly all federal retirees, because you paid the Medicare tax throughout your career. There's almost never a reason not to take Part A at 65.
- Part B (medical/doctor). Carries a monthly premium (set each year, and higher for high-income retirees under the IRMAA surcharge). This is the actual decision.
The deadline trap retirees fall into
This is the part to understand before you turn 65:
- If you're still working at 65 with FEHB through active employment, you can delay Part B without penalty and pick it up later through a Special Enrollment Period when you retire.
- If you're already retired (or you retire after 65), FEHB is no longer "active employment" coverage for this purpose — so it does not give you that special enrollment window. If you skip Part B around 65 and later change your mind, you can face a permanent late-enrollment penalty (added to your premium for life) and a wait until the next General Enrollment Period to get coverage.
So for most retirees, the decision is effectively "decide at 65" — not "decide whenever." That's what makes it worth thinking through in advance.
Keeping both vs. FEHB alone
| Keep FEHB + add Part B | Keep FEHB alone |
|---|---|
| Medicare becomes primary; FEHB secondary. Many FEHB plans waive deductibles and copays for members who have Part B, and a growing number reimburse part of the Part B premium. | You avoid the Part B premium. FEHB remains comprehensive on its own, and many retirees are perfectly well covered without Part B. |
| Often very low out-of-pocket costs and broad provider access. | Simpler, and cheaper month to month — but you carry FEHB's normal cost-sharing without a Medicare backstop. |
| Costs the Part B premium (plus IRMAA if high income). | If you ever want Part B later as a retiree, expect the late penalty. |
Reasonable, well-informed federal retirees go both ways on this. The right call depends on your specific FEHB plan's Medicare coordination (check whether it waives cost-sharing or reimburses Part B), your health, your income (IRMAA), and how much certainty versus monthly savings you want.
How to decide well
- Read your FEHB plan's Medicare section in its current plan brochure — coordination terms vary a lot between plans and change yearly.
- Mark your Initial Enrollment Period around your 65th birthday, and make a deliberate choice rather than letting it lapse.
- Factor in IRMAA if your income is high — it can raise the Part B premium substantially.
- Talk to SHIP or a licensed advisor if it's close. This is a personal decision with real money on both sides.
Plan the whole retirement picture, not just one election.
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