Medicare Parts A, B, C and D: What Each Part Covers

Part A: hospital insurance

Part A helps cover inpatient care in hospitals, skilled nursing facility care, hospice care, and home health care.

Many people qualify for premium-free Part A, and some have to buy it. If you have to buy Part A and do not sign up when you are first eligible, your monthly premium may go up 10%.

Part B: medical insurance

Part B helps cover services from doctors and other health care providers, outpatient care, home health care, durable medical equipment such as wheelchairs, walkers and hospital beds, and many preventive services, including screenings, shots or vaccines, and yearly Wellness visits.

You pay a monthly premium for Part B, and it can be higher depending on your income. For Part B services you usually pay 20% of the Medicare-approved amount after you meet your deductible. That share is called coinsurance. Original Medicare has no yearly limit on what you pay out of pocket, unless you have supplemental coverage or other insurance.

Part D: prescription drug coverage

Part D helps cover the cost of prescription drugs. You join a Medicare drug plan in addition to Original Medicare, or you get drug coverage by joining a Medicare Advantage plan that includes it. Plans that offer drug coverage are run by private insurance companies that follow rules set by Medicare.

If you join a separate drug plan, you pay a separate Part D premium. Joining late can add a penalty.

Part C: Medicare Advantage

Medicare Advantage, also called Part C, is an alternative to Original Medicare. You get your benefits through a private health plan that Medicare approved. These bundled plans include Part A, Part B, and usually Part D.

You may need to use doctors in the plan's network, and get approval, called prior authorization, for certain drugs or services before you receive them. Plans have a yearly limit on out-of-pocket costs, and most offer extra benefits that Original Medicare does not cover, such as vision, hearing and dental.

Medigap: a policy, not a part

Medicare Supplement Insurance, called Medigap, is extra insurance you can buy from a private company. It helps pay your share of costs in Original Medicare, such as your 20% coinsurance. Policies are standardized and, in most states, named by letters like Plan G or Plan K. The benefits in each lettered plan are the same no matter which company sells it.

You can buy Medigap to go with Original Medicare. You cannot buy it to cover out-of-pocket costs in a Medicare Advantage plan.

How the pieces fit together

When you first sign up, and during certain times each year, you choose between two main paths. Original Medicare includes Parts A and B, lets you use any doctor or hospital that takes Medicare, and can be paired with a separate Part D plan and a Medigap policy. Medicare Advantage replaces Original Medicare with a bundled private plan.

Our guide to Medicare Advantage vs Original Medicare compares the two paths side by side.

Common questions

Is Medicare Part C the same as Medicare Advantage?

Yes. Medicare Advantage is also called Part C. It is an alternative to Original Medicare, and the plans are offered by private companies that Medicare approves.

Do I need Part D if I have Medicare Advantage?

Most Medicare Advantage plans include Part D drug coverage, so you usually do not join a separate drug plan. Check that the plan you choose includes it.

Is Medigap one of the parts of Medicare?

No. Medigap is a separate policy sold by private companies that helps pay your share of costs in Original Medicare.