Federal Employee Health Benefits (FEHB) plans continue paying primary for retirees who do not enroll in Medicare Part B. FEHB is only secondary if you enroll in Part B. Whether to enroll in Part B or use FEHB as primary coverage is a personal decision, based on your individual circumstances. You should look at the costs and benefits of each insurance plan and make the choice that’s best for you. Questions to consider include:

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  • Which forms of insurance do your providers take?
  • Which kind of services do you use regularly?
  • Which coverage offers the flexibility you need?

If you decide to enroll in Part B, you should do so within eight months after you no longer have FEHB coverage from current employment. Review your FEHB plan brochure for more details. Note that you may be unable to enroll in FEHB again if you disenroll. If you stay enrolled in FEHB and also take Part B:

  • Medicare will be primary
  • FEHB may cover your Medicare cost-sharing (deductibles, copayments, coinsurances)

If you stay enrolled in FEHB and do not enroll in Part B:

  • Your FEHB plan will continue providing the same coverage it did when you were actively employed
  • Note that some individuals choose to enroll in Part A because it is premium-free but turn down Part B because of the additional monthly premium.
  • Those who want to enroll in Part B in the future may face penalties and have to wait to enroll during the General Enrollment Period (GEP)

Note: If you keep FEHB, you must continue paying full FEHB premiums, regardless of whether you take Medicare.

Remember, FEHB plans offer HMO and FFS options.

  • FEHB HMO plans have networks of providers and facilities
  • FFS plans allow you to see any provider, but you may pay higher costs

You should also compare the costs and benefits of your FEHB drug coverage and Part D to decide which best suits your needs.