Medicare Parts A, B, C, and D Explained Simply

Medicare doesn't have to be confusing. The problem is that most explanations start with the alphabet soup — Parts A through D — without explaining why the system is structured this way or what it means for you practically. Let me fix that.

Part A: Hospital Insurance

Part A covers inpatient hospital care, skilled nursing facility care, hospice, and some home health services. Most people pay $0 premium for Part A because they (or their spouse) worked and paid Medicare taxes for at least 10 years.

What Part A doesn't cover: outpatient care, doctor visits, prescriptions, or most dental and vision.

The catch: Part A has a deductible ($1,676 in 2025) per benefit period — not per year. If you're hospitalized twice in the same year with a gap in between, you could owe this deductible twice.

Part B: Medical Insurance

Part B covers doctor visits, outpatient care, preventive services, and medical equipment. The standard premium is $185/month in 2025, though higher earners pay more (called IRMAA surcharges).

Part B has an annual deductible ($257 in 2025), after which you typically pay 20% of covered services. That 20% has no cap — which is why most people need a supplement.

Part C: Medicare Advantage (the alternative)

Part C isn't a separate coverage layer — it's an alternative way to receive your Part A and B benefits through a private insurance company. Medicare pays the carrier a set amount; the carrier provides your coverage, usually with lower premiums but network restrictions.

We have strong opinions about when Advantage plans make sense and when they don't. The short version: if you're healthy and want low premiums, Advantage can work well. If you have ongoing care needs and want provider flexibility, a Supplement + Part B is usually better.

Part D: Prescription Drug Coverage

Part D is standalone prescription drug coverage, offered by private plans approved by Medicare. Plans vary enormously in which drugs they cover and at what cost. In 2025, the maximum out-of-pocket for Part D is $2,000 — a major improvement from prior years.

Critical rule: Don't pick a Part D plan based on the premium. Pick it based on whether it covers your specific medications at a cost you can afford. We run this comparison for every client.

What Most People Get Wrong

The most expensive Medicare mistake isn't picking the wrong plan — it's missing enrollment windows. Late enrollment penalties for Part B are permanent (10% per year you delayed), and for Part D they compound as well.

The second-most-expensive mistake: not getting a Medigap Supplement. The 20% coinsurance on Part B has no ceiling. One serious illness without a supplement can cost tens of thousands out of pocket.

Debbie Denesha

Medicare Specialist · Denesha Insurance Agency

Debbie works alongside Terry, helping clients navigate life insurance and benefits decisions with patience, clarity, and zero pressure.