Part C is an alternative way to get your Medicare coverage through a private insurance company instead of the government

Part C, also called Medicare Advantage, is a plan sold by private insurance companies that bundles your Part A (hospital) and Part B (doctor visits) coverage into one plan. You still pay your Part B premium to Medicare, but the insurance company becomes your main coverage provider. Most Part C plans also include prescription drug coverage (Part D) built in, so you do not need to buy it separately.

The trade-off is that Part C plans usually have a network — you must use doctors, hospitals, and specialists that are in the plan's network, except in emergencies. Many plans also charge a copay or coinsurance when you see a doctor or go to the hospital. In return, Part C plans often have lower monthly premiums than Original Medicare plus a separate Medigap policy, and they may cover services that Original Medicare does not, like dental, vision, or hearing aids.

Key Takeaways

  • Part C is sold by private insurance companies and covers both hospital and doctor visits in one plan, replacing Original Medicare coverage.
  • You must use doctors and hospitals in the plan's network, except in emergencies, or pay more out of pocket.
  • Most Part C plans include prescription drug coverage, so you do not buy Part D separately.
  • Part C plans often have lower premiums than Original Medicare plus Medigap, but may have higher copays and coinsurance at the point of care.
  • You can switch to or from Part C during the Annual Enrollment Period (October 15 to December 7 each year) or if you have a may have access to life event.

How Part C differs from Original Medicare

Original Medicare is run by the federal government and covers hospital care (Part A) and doctor visits (Part B) with no network restrictions — you can see any doctor or hospital that accepts Medicare. You pay a deductible and coinsurance, and you can buy a separate Medigap policy to cover some of those costs.

Part C is run by a private company and covers the same hospital and doctor services, but only through doctors and hospitals in that company's network. You pay a monthly premium to the insurance company (in addition to your Part B premium to Medicare), and you typically pay a copay or coinsurance each time you use a service. Because the insurance company is taking on the financial risk, it can offer lower premiums and extra benefits like dental or vision — but you lose the freedom to see any doctor you want.

If you choose Part C, you cannot also buy a Medigap policy. Medigap is designed to work with Original Medicare, not with Part C.

What Part C plans cover

All Part C plans must cover everything that Original Medicare covers: hospital stays, doctor visits, emergency care, and preventive services like screenings and vaccines. Beyond that, each plan is different. Some plans cover dental cleanings and exams, some cover vision exams and glasses, and some cover hearing aids or fitness programs. These extra benefits vary widely by plan and by region.

Most Part C plans include prescription drug coverage (Part D) at no extra cost. A few do not, but those are rare. If your plan does not include drug coverage, you can buy Part D separately, though you may face a late enrollment penalty if you wait.

All Part C plans have an out-of-pocket maximum — a yearly limit on what you will pay for covered services. Once you hit that limit, the plan pays 100 percent of covered services for the rest of the year. This out-of-pocket maximum varies by plan but provides a safety net that Original Medicare does not.

Network restrictions and how they affect your care

Part C plans use networks of doctors, hospitals, specialists, and other providers. If you see a doctor in the network, you pay the copay or coinsurance the plan sets. If you see a doctor outside the network, you usually pay much more — sometimes the full cost — unless it is an emergency.

Some Part C plans are HMOs (Health Maintenance Organizations), which means you must choose a primary care doctor and get a referral from that doctor to see a specialist. Other plans are PPOs (Preferred Provider Organizations), which let you see specialists without a referral but charge higher copays for out-of-network care. A few plans are PFFS (Private Fee-for-Service), which work more like Original Medicare but still require you to check whether a provider is in the plan.

Before you choose a Part C plan, check whether your current doctors are in the network. If your doctor is not in the plan, you will have to switch doctors or pay out of pocket.

Costs: premiums, copays, and out-of-pocket limits

Part C plans charge a monthly premium on top of your Part B premium. Some plans have a zero premium — you pay only your Part B premium to Medicare and nothing extra to the insurance company. Other plans charge $50 to $200 or more per month. The premium depends on the plan and your location.

When you use a service, you also pay a copay or coinsurance. A copay is a flat fee (for example, $15 to see a doctor). Coinsurance is a percentage of the cost (for example, 20 percent of the hospital bill). These amounts vary by plan and by type of service. You can see the copays and coinsurance for each plan before you choose.

Every Part C plan has an out-of-pocket maximum. In 2024, this maximum is set by Medicare and varies, but plans cannot charge more than a certain amount per year. Once you reach that limit, the plan pays 100 percent of your covered services for the rest of the year. This is different from Original Medicare, which has no out-of-pocket maximum.

When you can switch to or from Part C

You can change your Part C plan or switch to Original Medicare during the Annual Enrollment Period, which runs from October 15 to December 7 each year. Changes take effect on January 1. You can also switch if you have a may have access to life event, such as moving out of your plan's service area, losing other health coverage, or getting married or divorced. You have 60 days from the event to make a change.

If you are new to Medicare, you have a one-time Initial Enrollment Period of seven months centered on your 65th birthday. During this window, you can choose Original Medicare or Part C without penalty.

If you miss the Annual Enrollment Period and do not have a may have access to event, you cannot change your plan until the next October. The exception is if your plan is leaving Medicare or dropping your area — in that case, Medicare will send you a notice and give you a special enrollment period to switch.

How to compare Part C plans in your area

Medicare publishes a plan comparison tool on Medicare.gov where you can enter your zip code and see all the Part C plans available to you. The tool shows the monthly premium, copays, deductibles, out-of-pocket maximum, and which doctors and hospitals are in the network for each plan. You can also see which extra benefits (dental, vision, hearing, fitness) each plan offers.

Before you choose, make a list of your current doctors and medications. Then check whether each doctor is in the plan's network and whether each medication is on the plan's formulary (the list of covered drugs). If your doctor or drug is not covered, that plan may not be right for you.

You can also call 1-800-MEDICARE to speak with someone who can walk you through the plans available in your area and answer questions about coverage and costs.

Frequently Asked Questions

Can I use my Part C plan if I travel out of state?

Most Part C plans cover emergency care anywhere in the United States. For routine care, you must use doctors in the plan's network, which is usually limited to your state or region. If you travel frequently or spend winters in another state, ask the plan whether it has providers where you will be and whether you can see out-of-network doctors without a big cost increase.

What happens to my Part C coverage if I move?

If you move outside your plan's service area, the plan will end your coverage. Medicare will send you a notice and give you a special enrollment period to choose a new plan in your new location. You can switch to a different Part C plan or to Original Medicare without penalty.

Do I still have to pay my Part B premium if I have Part C?

Yes. You pay your Part B premium to Medicare every month, and then you may also pay a premium to the Part C insurance company. The Part B premium is deducted from your Social Security check (or you pay it directly to Medicare if you do not get Social Security).

Can I switch from Part C back to Original Medicare anytime I want?

You can switch during the Annual Enrollment Period (October 15 to December 7) or if you have a may have access to life event like moving or losing coverage. Outside these windows, you cannot switch unless your plan is leaving Medicare or you have a may have access to event. If you switch to Original Medicare, you may want to buy a Medigap policy to cover costs that Original Medicare does not.

What if my Part C plan drops a doctor I need?

If your doctor leaves the plan's network mid-year, the plan must notify you. You can then switch to a different Part C plan or to Original Medicare during a special enrollment period without waiting for the Annual Enrollment Period. Contact the plan or call 1-800-MEDICARE to report the change and ask about your options.