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How Do Medicare And FEHB Work Together?

Written by 
Molly Burford

Article at a glance

  • The federal employee health benefits (FEHB) program provides health insurance for federal government employees or retirees and their families. 

  • Medicare is a government healthcare program for those 65 and older, younger Americans with disabilities, or those with end-stage renal disease (ESRD).

  • Medicare coverage can be combined with FEHB coverage. FEHB will be the beneficiary’s primary coverage until retirement. 

The Federal Employees Health Benefits (FEHB) Program is the largest employer-sponsored group health insurance program in the world. FEHB plans provide health coverage for almost 9 million people, including United States federal employees and annuitants, as well as their family members. Former spouses and former employees may also be eligible for coverage in certain situations. 

For government employees who are, or will soon be, eligible for Medicare, there may be questions about how the two programs work together, and if enrollment in both programs is necessary. 

While federal retirees or active employees do not have to enroll in both Medicare and FEHB, at times there are benefits in having coverage from both. For some beneficiaries, having FEHB and Medicare may help save them money in addition to creating more comprehensive healthcare coverage. This article will explain when and how to enroll in FEHB and a Medicare plan along with other aspects of Medicare and FEHB coverage you may need to consider.

What Are Federal Employee Health Benefits?

FEHB plans are part of a healthcare program created for federal employees to provide health insurance for workers and their family members. Plans available through the FEHB program include: 

  • Fee-for-service plans (FFS): A fee-for-service plan is a health insurance plan that requests payment from doctors and patients for each service received at a medical practice.

  • Health Maintenance Organizations (HMOs): HMO plans are one of the most popular insurance plans as they require a PCP, provide a network of providers and practices, and overall offer a structured health care plan for patients.

  • Point of Service (POS) product plans: POS plans offer a similar structure to HMO plans, although they provide more flexible coverage to patient that wants to explore providers or practices that are out-of-network.

Note: FEHB provides a vast array of healthcare plans to choose from. Compare plans at this resource.

What is Medicare?

Medicare is a government health benefits program that provides health insurance for those 65 and older, younger Americans with disabilities, or those with end-stage renal disease (ESRD). There are various types of Medicare available for enrollment. 

Some Medicare benefits programs are: 

  • Original Medicare plans

  • Medicare Advantage (MA) plans (Medicare Part C)

  • Medicaid-Medicare (Dual-Enrollment Program) plans

  • Medicare supplement plans (Medigap)

There are various parts to Medicare, each one responsible for coverage for specific health care services.

Medicare Part A

Medicare Part A is Medicare’s hospital insurance. Medicare Part A provides coverage for the following services: 

  • Inpatient hospital care

  • Skilled nursing facility care

  • Nursing home care (non-custodial or long-term care)

  • Hospice care

  • Home health care

Enrollment for Medicare Part A coverage is usually automatic if you are 65 and have worked for 10 years while paying Medicare taxes. 

Medicare Part B

Medicare Part B is Medicare’s medical insurance. If you choose to enroll in Part B, coverage consists of two main types of covered services:

  • Medically-necessary care

  • Preventative services (i.e. vaccinations)

Medicare Part B comes at a premium rate that varies depending on your income. This premium is often taken out of your Social Security or Railroad Retirement check monthly.

Medicare Advantage Plans (Medicare Part C)

Medicare Part C is Medicare Advantage plans, also known as MA plans. Part C is provided through private insurance companies. Essentially, Medicare Advantage plans are enhanced versions of Original Medicare, meaning these types of health plans provide both Medicare Part A and Part B, in addition to other benefits, sometimes prescription drugs. 

Note: Learn more about what Medicare Part C is at this resource.

Medicare Part D 

Medicare Part D is Medicare prescription drug coverage. Enrollment for Medicare Part D is not automatic. Medicare beneficiaries must either enroll in a separate Medicare drug plan or find a Medicare Advantage plan that includes drug coverage. Do note that not all MA plans provide coverage for prescription medications. 

How Do FEHB Plans and Medicare Plans Work Together?

Medicare and FEHB can be coordinated. Knowing when each plan is the primary payer or the secondary payer will be vital to understanding how this coordination functions. Learn when each one is which at this resource.

Should Someone Combine FEHB With Medicare?

Active or retired federal employees currently enrolled, or eligible, for Medicare can coordinate Medicare coverage with their FEHB coverage. In fact, at times it is recommended to do so because having both health insurances can provide federal or active government employees with more comprehensive healthcare coverage. Of course, individual circumstances in both health and finances will ultimately be the determining factor in if it makes sense to do so.

While FEHB plans generally cover the same services as those within Medicare, FEHB does provide coverage for services Medicare does not, and vice versa. For example, FEHB covers emergency care outside of the U.S., and Medicare does not. As well, some FEHB plans also cover dental and vision services. Medicare does cover some orthopedic and prosthetic services, durable medical equipment, home health care, limited chiropractic services, and certain medical supplies, which some FEHB plans may only partially cover (or not at all). 

FEHB and Prescription Drugs

All FEHB plans provide prescription drug coverage. As such, Original Medicare beneficiaries who choose to combine health care with FEHB do not need to enroll in Medicare Part D because they will already have prescription drug benefits. 

However, if an enrollee does combine FEHB and Medicare Part D, Medicare acts as the primary payer with FEHB acting as the secondary. This means that Medicare receives claims first and FEHB will review and cover claims of the prescription drug costs that were not covered by Medicare.

Understanding The Costs

All FEHB plans provide prescription drug coverage. As such, Original Medicare beneficiaries who choose to combine health care with FEHB do not need to enroll in Medicare Part D. 

That said, if a Medicare beneficiary loses or unenrolls in FEHB coverage, they will have to pay a higher premium for Medicare part D if they go without equivalent prescription drug coverage for a period of 63 days or longer. Learn more at this Office of Personnel Management resource.

Aside from prescription drug costs, there might be other premiums and out of pocket costs associated with Medicare and FEHB coverage that vary based on the plan chosen. It’s important to speak with your insurance provider to fully understand your benefits and what’s covered by your provider.

What Else to Know:

  • FEHB plan brochures explain exactly what services and supplies are covered, as well as the level of coverage. Each brochure is formatted in the same way, so these are easy to read. Review 2022 FEHB plan brochures here.


Can I enroll in Medicare Advantage if I have FEHB?

Yes, although you might not need FEHB if you enroll in an MA plan. FEHB is designed to help pay for costs not covered by Original Medicare, similar to an MA plan. Be sure to check each plans benefits before enrolling in one or dropping the other to ensure you’re receiving the most practical coverage possible.

How do I keep FEHB throughout retirement?

There are two requirements to keep FEHB through your lifetime:

  • You must be eligible for an immediate pension (annuity)

  • You must have been continuously enrolled in FEHB for 5 years prior to your pension (annuity) starting

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