Medicare is the federal health insurance program for people who are 65 or older, certain younger people with disabilities, and people with End-Stage Renal Disease (permanent kidney failure requiring dialysis or a transplant, sometimes called ESRD).

What are the different parts of Medicare, and how do they differ?

Medicare Part A (Hospital Insurance) covers inpatient hospital stays, skilled nursing facility care, hospice care, and some home health care.

Medicare Part B (Medical Insurance) covers certain doctors' services, outpatient care, medical supplies, and preventive services.

Medicare Part D (Prescription Drug Coverage) helps cover the cost of prescription drugs (including recommended shots or vaccines).

How Does Medicare Work?

Original Medicare includes Medicare Part A (Hospital Insurance) and Medicare Part B (Medical Insurance). You pay for services as you get them. When you get services, you pay a deductible at the start of each year, then pay 20% of the cost of Medicare-approved service, called coinsurance. If you want drug coverage, you can add a drug plan (Part D). Original Medicare pays for much, but not all, of the cost for covered health care services and supplies.

Medicare Supplement Insurance (Medigap) is a policy designed to help pay some of the remaining health care costs, like copayments, coinsurance, and deductibles. Medigap policies also cover services that Original Medicare doesn't cover, like medical care when you travel outside the U.S.

Medicare Advantage is an “all in one” alternative to Original Medicare. These “bundled” plans include Part A, Part B, and usually Part D. Most plans offer extra benefits that Original Medicare doesn’t cover — like vision, hearing, dental, and more. Medicare Advantage Plans have yearly contracts with Medicare and must follow Medicare’s coverage rules. The plan must notify you about any changes before the start of the next enrollment year. Each plan can charge different out-of-pocket costs. They may also have different rules for how you get services.