Medicare Parts A, B, C, and D: The Complete Breakdown

Understanding Medicare starts with knowing the alphabet. Medicare is divided into four main parts: A, B, C, and D. Each part covers a different aspect of your healthcare, and knowing how they work together is the first step to making sure you have the right coverage in place.

The most important thing to understand is that you are choosing between two distinct paths, not just picking products off a shelf. The real choice is between Traditional Medicare (Parts A and B) and Medicare Advantage (Part C). Let's walk you through every option so you can make an informed decision.

Part A: Hospital Insurance

Medicare Part A is the foundation of your coverage. It helps pay for inpatient care in a hospital, skilled nursing facility care, hospice care, and some home healthcare. For most people, Part A is premium-free as long as you or your spouse paid Medicare taxes while working for at least 10 years (40 quarters). If you don't meet that requirement, you can still buy Part A, but you will pay a monthly premium [as of 2026, varies by location and age].

While Part A covers a lot, it doesn't cover everything. You will still be responsible for deductibles and coinsurance when you use these services.

Part B: Medical Insurance

Medicare Part B covers the services and supplies that are medically necessary to treat your health condition. This includes outpatient care, preventive services, ambulance services, and durable medical equipment. Unlike Part A, everyone pays a monthly premium for Part B. The standard premium is set by the government each year, but if your income is above a certain threshold, you may pay an Income-Related Monthly Adjustment Amount (IRMAA).

Together, Parts A and B make up Traditional Medicare. This is the original program created by the federal government. With Traditional Medicare, you can see any doctor or visit any hospital in the country that accepts Medicare. However, Traditional Medicare does not have an out-of-pocket maximum, which means your financial risk is uncapped. This is why many people choose to add a Medicare Supplement (Medigap) plan to fill the gaps left by Parts A and B.

Part C: Medicare Advantage

Medicare Part C, also known as Medicare Advantage, is the alternative path to Traditional Medicare. These plans are offered by private insurance companies approved by Medicare. When you enroll in a Medicare Advantage plan, you still have Medicare, but you get your Part A and Part B coverage through the private plan instead of the federal government.

Most Medicare Advantage plans also include Part D prescription drug coverage, and many offer extra benefits like dental, vision, and hearing coverage. However, these plans typically require you to use a network of doctors and hospitals (like an HMO or PPO), and you may need prior authorization for certain services. The trade-off is that Medicare Advantage plans have a yearly limit on your out-of-pocket costs for medical services.

Remember, the supplement decision comes AFTER you choose Traditional Medicare - it's a component of the Traditional path, not an alternative to Advantage. If you choose Medicare Advantage, you cannot also have a Medigap plan.

Part D: Prescription Drug Coverage

Medicare Part D helps cover the cost of prescription drugs. Like Part C, these plans are offered by private insurance companies. If you choose the Traditional Medicare path, you will need to purchase a standalone Part D plan to get drug coverage. If you choose the Medicare Advantage path, your drug coverage is usually included in the plan.

Part D plans have their own premiums, deductibles, and copayments, which vary depending on the plan you choose and the medications you take. It's important to review your drug coverage every year during the Annual Enrollment Period to make sure your plan still meets your needs.

At Patriot Plans, we believe in straight answers, no surprises. We know that navigating Medicare can be overwhelming, but you don't have to do it alone. We are on your side of the table, ready to help you compare your options and find the coverage that fits your life.