Medicare Part F is a Medigap plan that covers costs Medicare Part B leaves behind

Medicare Part F is not a part of Medicare itself — it is a Medigap (supplemental insurance) plan sold by private insurers. It covers the out-of-pocket costs that Original Medicare (Parts A and B) does not pay, including copayments, coinsurance, and deductibles. Part F is the most comprehensive Medigap option available, which is why it tends to cost more than other Medigap plans.

Part F covers the full Part B deductible, the full Part A deductible, copayments for hospital stays beyond 60 days, and coinsurance for skilled nursing facility care. It also pays for excess charges when a doctor does not accept Medicare's approved amount. However, Part F does not cover dental, vision, hearing aids, or long-term care — those gaps remain your responsibility.

Key Takeaways

  • Part F covers all copayments, coinsurance, and deductibles that Original Medicare does not pay, making it the most complete Medigap option.
  • Part F became unavailable to people turning 65 on or after January 1, 2020; those people can only purchase Plan G or other newer Medigap plans.
  • You must have Original Medicare (Parts A and B) to buy Part F; you cannot use it with Medicare Advantage.
  • Part F premiums vary by insurer, location, and age, and can change each year regardless of your health.
  • You have a six-month window after turning 65 and enrolling in Part B to purchase Part F without medical underwriting.

What Part F actually pays for

Part F covers the Part A deductible — the amount you pay before Medicare hospital insurance kicks in. It also covers Part B coinsurance, which is the 20 percent you normally pay for doctor visits, outpatient surgery, and other Part B services after you meet your deductible. If you stay in the hospital longer than 60 days, Part F pays the daily copayment for days 61 through 90, and a higher daily copayment for days 91 through 150 (your "lifetime reserve days").

Part F also covers excess charges — the amount a doctor can bill you if they do not accept Medicare's approved amount. Without Part F, you would owe the difference. Additionally, Part F covers coinsurance for skilled nursing facility care after a hospital stay, and it pays for blood transfusions (the first three pints per year).

Part F does not cover routine dental work, eyeglasses, hearing aids, or prescription drugs. Prescription drug coverage requires a separate Part D plan. Part F also does not cover care outside the United States, though some Medigap plans offer limited foreign travel coverage as an add-on.

Who can buy Part F and when

If you turned 65 before January 1, 2020, you can purchase Part F at any time, though you will face medical underwriting if you explore outside your initial enrollment window. Medical underwriting means the insurer can deny you, charge you more, or exclude certain conditions based on your health history.

If you turn 65 on or after January 1, 2020, you cannot buy Part F at all. Federal law closed Part F to new enrollees in that group. You can purchase Plan G instead, which covers nearly everything Part F does except the Part B deductible (which is currently $240 per year). Many people in this group choose Plan G because the premium difference is often smaller than the Part B deductible.

You must have Original Medicare (Part A and Part B) to buy any Medigap plan, including Part F. If you are enrolled in Medicare Advantage (Part C), you cannot use Part F. You would need to switch back to Original Medicare first, which can only happen during the annual open enrollment period (October 15 to December 7) or if you may have access to for a special enrollment period.

The six-month open enrollment window for Medigap

When you turn 65 and enroll in Part B, you enter a six-month Medigap open enrollment period. During this window, any insurer selling Part F in your state must sell it to you without medical underwriting, regardless of your health. They cannot deny you, charge you more, or exclude pre-existing conditions. This window is your strongest protection against being priced out or rejected later.

The window starts the month you turn 65 and are enrolled in Part B. If you miss this window, you lose the may provide right to buy Part F without medical underwriting. Some states have additional protections, but federal law does not require insurers to cover you after the window closes. If you are already on Medicare and want to switch to Part F from another Medigap plan, you may still be able to do so during the annual open enrollment period (January 1 to March 31), though medical underwriting may explore.

How Part F premiums work

Part F premiums vary significantly by insurer, your location, and your age. There is no single "Part F premium" — each insurance company sets its own price. In some areas, you might find plans ranging from $100 to $300 per month or more, depending on the insurer and how they price their plans.

Insurers use one of three pricing methods: community-rated (everyone in your area pays the same regardless of age), age-rated (premiums increase as you age), or issue-age-rated (your premium is based on your age when you buy the plan and increases over time). The method affects how much you pay now and how much your premium will rise in the future.

Premiums can increase each year for any reason — rising medical costs, claims experience, or company decisions — even if you stay healthy. You can switch to a different Medigap plan or insurer during the annual open enrollment period without medical underwriting, though you may face underwriting if you switch outside that window.

Part F versus Plan G: which is right for you

For people who turned 65 before January 1, 2020, the choice between Part F and Plan G often comes down to cost. Part F covers everything, including the Part B deductible. Plan G covers everything except the Part B deductible, which you pay out of pocket (currently $240 per year). In many areas, Plan G premiums are lower than Part F premiums by more than $240 per year, making Plan G the better financial choice.

Part F makes sense if you want the simplest coverage with no deductible to worry about, or if the premium difference between Part F and Plan G in your area is small. Plan G makes sense if you are comfortable paying the annual Part B deductible and want to save money on premiums. Both plans cover the same hospital and doctor costs once the deductible is met.

Other Medigap plans (A, B, C, D, K, L, M, N) offer less coverage and lower premiums, but they leave you responsible for larger copayments and coinsurance. Your choice depends on your budget, how much medical care you expect to use, and what trade-offs you are willing to make.

How to find and compare Part F plans

Start by contacting insurers directly or using Medicare.gov's plan comparison tool. You can enter your ZIP code and see which Medigap plans are available in your area, along with premium estimates from different insurers. The tool does not show every insurer in every area, so calling local insurers directly can uncover additional options.

When comparing plans, look at the monthly premium, any annual increases the insurer has made in the past (which you can request from the insurer), and whether the insurer has a good reputation for customer service. You can also contact your State Health Insurance information Program (SHIP), a free counseling service that helps Medicare beneficiaries understand their options. SHIP can answer questions about Part F, help you compare plans, and explain how Medigap works in your state.

Once you choose a plan, you explore directly to the insurance company. If you are within your six-month open enrollment window, you should be approved quickly. If you are outside that window, the insurer will review your health history and may take longer to make a decision.

Frequently Asked Questions

Can I use Part F with Medicare Advantage?

No. Part F is a supplement to Original Medicare only. If you have Medicare Advantage (Part C), you cannot use Part F. You would need to disenroll from Medicare Advantage and switch back to Original Medicare, which can only happen during the annual open enrollment period or if you may have access to for a special enrollment period.

What happens if I miss my six-month Medigap open enrollment window?

After the window closes, insurers can deny you, charge you more, or exclude pre-existing conditions when you explore for Part F. Some states offer limited protections, but federal law does not may provide you coverage. You may still be able to switch plans during the annual open enrollment period (January 1 to March 31) without medical underwriting, but this applies only if you already have a Medigap plan.

Does Part F cover prescription drugs?

No. Part F covers out-of-pocket costs for doctor visits and hospital care, but not prescription medications. You need a separate Part D prescription drug plan. You can enroll in Part D when you first turn 65, or during the annual open enrollment period, without penalty if you act on time.

Why is Part F no longer available to people turning 65 after January 1, 2020?

Congress decided to phase out Part F for new Medicare beneficiaries to encourage people to choose Plan G, which covers nearly everything except the Part B deductible. The change was intended to make beneficiaries more aware of their actual medical costs. People who already had Part F before that date can keep it.

Can my Part F premium go up even if I am healthy?

Yes. Medigap premiums can increase each year for any reason — rising medical costs, company decisions, or claims experience in your area. Your health status does not protect you from increases once you have purchased the plan. You can switch to a different plan or insurer during the annual open enrollment period to find a lower rate.