Medicare Parts A, B, C and D explained
Four letters, four jobs. Here's what each one does.
Medicare is divided into lettered parts that each cover a different kind of care. Understanding what each part does, and who provides it, is the quickest way to make sense of every other Medicare decision.
Part A: hospital insurance
Part A helps pay for inpatient care in a hospital, care in a skilled nursing facility after a qualifying hospital stay, hospice care and some home health care. Most people pay no premium for it. In 2026 you pay a $1,736 deductible for each benefit period before Part A pays, plus daily coinsurance for long stays.
Part B: medical insurance
Part B covers doctors' services, outpatient hospital care, preventive services, lab tests, mental health care, ambulance services and durable medical equipment. The standard premium is $202.90 a month in 2026, the deductible is $283 a year, and after that you usually pay 20% of the Medicare-approved amount, with no yearly cap in Original Medicare.
Part C: Medicare Advantage
Part C isn't extra coverage on top of A and B. It's another way to get them. A Medicare Advantage plan is run by a private company that contracts with Medicare and must cover everything Original Medicare covers, though it can use different rules, networks and cost sharing. Most plans include Part D drug coverage, and many add limited extras such as dental or vision.
You still pay your Part B premium, plus any premium the plan charges. Every plan has a yearly limit on what you pay for covered Part A and B services: no more than $9,250 for in-network care in 2026, and many plans set theirs lower.
Part D: prescription drug coverage
Part D is sold by private plans, either as a standalone drug plan that works with Original Medicare or inside a Medicare Advantage plan. Each plan has its own list of covered drugs (a formulary), premium and cost sharing. In 2026, your out-of-pocket costs for covered drugs are capped at $2,100 for the year, and the deductible can be no more than $615.
How the parts combine
There are two common setups:
- Original Medicare: Part A + Part B + a standalone Part D plan, often with a Medigap policy to cover some out-of-pocket costs.
- Medicare Advantage: Part A and Part B delivered through a Part C plan, which usually includes Part D.
| Original Medicare | Medicare Advantage | |
|---|---|---|
| Who runs it | The federal government (A and B) | A private company approved by Medicare |
| Doctors | Any provider in the US that accepts Medicare | Usually a network; rules vary by plan type |
| Yearly out-of-pocket limit | None, unless you add Medigap | Yes, up to $9,250 in-network in 2026 |
| Drug coverage | Add a standalone Part D plan | Usually included |
| Can add Medigap? | Yes | No |
Common questions
Most people take both. You may be able to delay Part B without a penalty if you or your spouse are still working and covered by an employer's group plan. You need both A and B to join a Medicare Advantage plan or buy Medigap.
No. Part C (Medicare Advantage) replaces Original Medicare's way of paying for care. Medigap is a separate policy that helps pay costs Original Medicare leaves behind. You can't use them together.
There's no Part E. "Plan F" and "Plan G" are Medigap policies, named with letters that have nothing to do with the parts of Medicare.
Want help with your own choices?
Every state runs a State Health Insurance Assistance Program (SHIP) with trained counselors who give free, unbiased Medicare help and do not sell plans. Find yours on our Medicare by state pages, or call Medicare at 1-800-MEDICARE (1-800-633-4227) (TTY 1-877-486-2048, 24 hours a day, 7 days a week).
Planning the rest of your coverage in retirement? We can help with life insurance later in life and final expense coverage.
Sources
- 2026 Medicare Parts A & B Premiums and Deductibles, Centers for Medicare & Medicaid Services. Checked September 29, 2026.
- Medicare costs, Medicare.gov. Checked September 29, 2026.
- Costs for Medicare drug coverage, Medicare.gov. Checked September 29, 2026.
- Final CY 2026 Part C Bid Review Memorandum, Centers for Medicare & Medicaid Services. Checked September 29, 2026.
General information about the federal Medicare program, not advice about your situation. Figures are for 2026 unless stated and change every year; last reviewed September 29, 2026. Quote My Policy is a private company. Not connected with or endorsed by the United States government or the federal Medicare program.
Quote My Policy does not sell Medicare plans on this site. For plan-specific help, contact Medicare at 1-800-MEDICARE (1-800-633-4227) (TTY 1-877-486-2048, 24 hours a day, 7 days a week) or your State Health Insurance Assistance Program.