Medicare Part C (Medicare Advantage)

Medicare Part C (Medicare Advantage)

August 09, 2023

What is Medicare Part C (Medicare Advantage)?

A Medicare Part C (Medicare Advantage) plan is offered by a private company that contracts with Medicare to provide Part A and Part B benefits and may offer coverage for additional services.

When Medicare was created in 1965 (Original Medicare), it provided only two parts; Part A and Part B. Generally speaking, Part A is free to eligible recipients and helps pay for in-hospital care. Part B is optional and helps pay for regular medical care (e.g., doctor's bills, X-rays, lab tests). Individuals who choose to enroll in Part B must pay a premium, a deductible, and co-payments.

Original Medicare is a private fee-for-service (PFFS) plan, which means that beneficiaries can choose any doctor or specialist who accepts Medicare, and is available nationwide. Original Medicare is administered directly by the federal government, although claims and payments flow through private health insurance companies that act as intermediaries.

In 1997, Medicare Part C (originally called Medicare + Choice) became available to persons who are eligible for Part A and enrolled in Part B. Under Part C, private health insurance companies can contract with the federal government to offer Medicare benefits through their own policies. Insurance companies that do so are able to offer Medicare beneficiaries health coverage not only through PFFSs, but also through managed care plans (such as HMOs) and preferred provider organizations (PPOs). Medicare beneficiaries may also be able to enroll in Medicare Medical Savings Account Plans (Medicare MSAs) or HMO Point-of-Service Plans if available in their area.

Insurance companies can offer Medicare recipients benefits that are not covered under Original Medicare, although a premium may be charged for the extra coverage. Further, managed care plans and PPOs can typically offer Medicare recipients benefits at a lower cost because enrollees can only get covered health care through the plan's network of providers, allowing the insurance company to "manage" the costs. The result is that many Medicare beneficiaries (some plans are not available in all areas) have a wider array of health plan options from which they can choose, allowing them to obtain the best coverage they can get at a cost they can afford.

In 2003, under the Medicare Prescription Drug, Improvement, and Modernization Act, Medicare Advantage became the new name for Medicare + Choice plans, and certain rules were changed to give Part C enrollees better benefits and lower costs. The law also created Part D, prescription drug coverage.

In 2010, health-reform legislation made several changes to Medicare Advantage plans, including eliminating subsidies paid to plans, changing open enrollment periods, and strengthening protections for beneficiaries.

A toll-free number ((800) MEDICARE) and a website ( are available to answer questions you may have about your Medicare benefits and direct you to publications where you can find more information. The Medicare Health Plan Compare tool available on the website also allows you to find and compare health plans that are available in your area.

You can also get free, personalized help from a trained counselor by contacting your State Health Insurance Assistance Program (SHIP). Your SHIP counselor can help you review your Medicare options or help explain Medicare coverages and guidelines. To find your local SHIP, visit the SHIP National Network at or call 877-839-2675.

The federal government now offers Medicare benefits through PPOs (not to be confused with Medicare Advantage PPOs) as well as through PFFSs.

Enrolling in a Medicare Advantage plan

In order to enroll in a Medicare Advantage plan, you must be entitled to Part A and enrolled in Part B, and you can only enroll in a plan that is available in your area. If you're new to Medicare, you can generally enroll when you first become eligible (three months before the month you turn 65 until three months after the month you turn 65). However, once you're enrolled in a Medicare Advantage plan, you can generally make changes to your plan only during certain time periods.

Currently, one such period occurs from October 15 through December 7 of each year. During this time period (referred to as open enrollment), you can select a new Medicare health plan and/or a Medicare prescription drug plan or make other changes to your coverage for the following year. If you're enrolled in a Medicare Advantage plan as of January 1, you also have an opportunity to disenroll and return to Original Medicare with or without a prescription drug plan, or switch to a different Medicare Advantage plan with or without drug coverage between January 1 and March 31 (the General Enrollment Period). Other special enrollment periods may also be available. For more information about when you can join or switch Medicare plans, call (800) Medicare.

Individuals with end stage renal disease may enroll in Medicare Advantage plans.

Why choose a Medicare Advantage plan?

Medicare Advantage is an "all-in-one" alternative to Original Medicare. When you enroll in any Medicare Advantage plan, you will still get all Original Medicare covered services, but you may also obtain extra benefits and services not offered by Original Medicare, and/or you may be able to reduce your out-of-pocket costs. The extra benefits and services you receive and/or the amount of money you save will depend on which Medicare Advantage plan you choose. Most Medicare Advantage plans include Part D prescription drug coverage.

Because out-of-pocket costs and the types of coverage offered will vary, it's important to compare plans before choosing one. Because private insurance companies offer Medicare Advantage plans, they can change the extra benefits provided by the plan and decide (on an annual basis) whether they will continue participating in Medicare. Health care providers can also join or leave the plan at any time.

Several types of Medicare Advantage plans may be available in your area. These include Medical Savings Account (MSA) plans, Special Needs Plans (SNPs), the three types discussed below--Private Fee-for-Service (PFFS) plans, Health Maintenance Organization (HMO) plans, and Preferred Provider Organization (PPO) plans--and others.

You can't use (and can't be sold) a Medigap policy if you're in a Medicare Advantage plan, so you may decide to cancel an existing Medigap policy because you will no longer need the extra coverage the policy provides. However, you should be aware that if you do so, you may be unable to get it back except in certain situations. If you've just become eligible for Medicare or if it is the first time you've enrolled in a Medicare Advantage plan, you may have special Medigap protections.

Medicare Advantage Private Fee-for-Service (PFFS) plans

These plans are generally the most flexible and most costly. They allow you to see any Medicare-approved health care provider who accepts the terms of your plan.

Medicare Advantage Health Maintenance Organization (HMO) plans

You may save the most money on your health costs by joining a Medicare Advantage managed care plan--a Health Maintenance Organization (HMO) plan. However, your choice of health care providers is more limited than with other options--you're generally covered only when you see doctors and specialists, or go to hospitals that are part of the plan's network of providers, within the plan's service area. When you choose a Medicare Advantage HMO, you'll need to choose a primary care physician who will oversee your care and refer you to specialists when necessary. With some HMO plans, you may be able to go out of network for certain services, usually at a higher cost. This type of plan is called an HMO with a point-of-service option (HMOPOS).

Medicare Advantage Preferred Provider Organization (PPO) plan

With Medicare Advantage PPOs, you will generally only see health care providers within the plan's network, but, unlike Medicare Advantage managed care plans, you can choose doctors and services outside the PPO network usually for a fee, and you do not need to choose a primary care doctor or get referrals to see specialists.

Choosing the right Medicare Advantage plan

There's a lot to consider when deciding which Medicare option is right for you. Here are some questions to ask during the decision-making process:

  • How much is the premium?
  • Will you need to satisfy a deductible or pay co-payment or coinsurance costs? Medicare Advantage plans have an annual cap on how much you pay for Part A and Part B services. This will differ among plans.
  • Does the plan cover the extra benefits or services you need (such as coverage for vision, hearing, dental, or health and wellness programs)? Does the plan offer prescription drug coverage (most Medicare Advantage plans do)?
  • Do the health care providers you normally see participate in the plan?

What if your Medicare Advantage plan leaves the Medicare program?

You still have Medicare coverage. You can return to Original Medicare or join another Medicare Advantage plan if one is available where you live. Your options will be listed in the notification letter you are sent when your plan leaves the Medicare program.

Consumer protections under Medicare Part C

Under Medicare Part C, consumers are offered several protections designed to enhance the quality of care they receive, including the right to information, the right to participate in treatment decisions, the right to get emergency services, and the right to file complaints. In addition, your state insurance laws may provide additional consumer protections.

What are your appeal rights?

You have the right to appeal any decision about your Medicare-covered services, whether you are enrolled in Original Medicare or a Medicare Advantage plan. You can file an appeal if your plan does not pay for or provide a service or item you think should be covered or provided. The appeal procedure may vary, depending on the type of Medicare plan you have. If you are enrolled in Original Medicare, you can find your appeal rights on the back of the Explanation of Medicare Benefits or Medicare Summary Notice you received. If you are enrolled in a Medicare Advantage plan, the plan must give you written notification of your appeal rights; this will generally be included in your Medicare enrollment materials.

Medicare beneficiaries also have the right to a fast-track appeals process. If you believe that your health plan is ending its services too soon, you can ask for a quick review of your case conducted by independent doctors. You may have additional rights if you are hospitalized, in a skilled nursing facility or if your home health care ends.

If you have any questions about consumer protections or appeal rights, call (800) Medicare or visit the Medicare website.