What are the different parts of Medicare?

Medicare consists of several programs, known as parts, working together to help you meet your healthcare needs.¹ Parts A and B are often referred to as original Medicare.

What’s Part C (Medicare Advantage)?

You might notice that Part C isn’t shown. That’s because Part C, also known as Medicare Advantage, is a bit different. It’s a Medicare-approved plan offered by private insurance companies as an alternative to original Medicare.¹ Depending on the plan, it may include Part D in addition to Parts A and B, and even extra benefits such as dental, vision, and hearing coverage.

The types of Medicare Advantage plans include:

• Health maintenance organization (HMO)
• Medical savings account
• Preferred provider organization (PPO)
• Private fee for service
• Special needs plan

There are advantages and disadvantages to both original Medicare and Medicare Advantage. An insurance or financial professional can help you understand and evaluate your options based on your location, healthcare needs, and budget.

What’s Medigap?

Medigap often comes up in conversations about Medicare, so you may think it’s part of the program, but it’s not. It’s a separate insurance policy you can buy to help pay for medical expenses that Medicare doesn’t cover. If you choose original Medicare, consider adding a Medigap policy to help reduce your out-of-pocket expenses. You can’t have both Medigap insurance and a Medicare Advantage plan.

How much does Medicare cost?

Although your paychecks help fund Medicare, it doesn’t mean coverage is free. How much you pay depends on many factors, including your type of coverage and income.

Here are some things to consider when reviewing your options²:

• Premiums—The monthly amount you pay for your Medicare coverage
• Deductibles—The amount you have to pay out of your pocket each year for covered medical expenses before Medicare or your Medicare Advantage plan starts paying
• Co-payment—The fixed amount you pay for a Medicare-covered service, such as $40 per doctor visit
• Coinsurance—The portion you have to pay after meeting your deductible. For example, Medicare Part B may cover 80% of a covered service, leaving you responsible for the other 20%

Learn more about Medicare costs.

Medicare and Medicare Advantage cover a lot, but they don’t cover everything, such as long-term care, which means you may have to pay for certain services yourself. Consider earmarking some of your retirement savings just for healthcare, so it’s there when you need it.

When do you enroll in Medicare?

Your initial Medicare enrollment period begins three months before the month when you turn 65 and ends three months after. For example, if you turn 65 in February, your enrollment period would be November 1 to May 31. Signing up late may result in higher premiums for Parts A, B, and D. You can wait to enroll in Parts B and D without penalty, however, if you still have health insurance through your employer or your spouse’s employer.   

Can you change your Medicare coverage?

You generally have to stick with your Medicare plan for the whole year, but you can change it during open enrollment. This usually happens every year from October 15 to December 7. During this time, you can pick a different plan for next year if you think there’s one that better fits your needs and budget.

What’s Medicaid? And can you have both Medicare and Medicaid?

It’s possible to have both Medicare and Medicaid if you qualify. Medicaid is a joint federal and state health program for people with limited income. Each state has its own rules, so you’ll need to check the requirements in your state to see if you’re eligible for Medicaid. If you have both, Medicare typically pays first for Medicare-covered services, then Medicaid.³      

Plan today to help make the most of Medicare tomorrow

Healthcare is one of the largest expenses you may face in retirement, especially as you get older. Medicare can help cover the costs, potentially leaving you with more money for your other needs and activities. Be sure to evaluate your options carefully and sign up on time. You’ve supported Medicare throughout your working years—now it’s time to enjoy the benefits.

1 “Parts of Medicare,” medicare.gov, October 2025. 2 “What does Medicare cost?”, medicare.gov, October 2025. 3 “A Quick Guide to Medicare & Medicaid,” medicare.gov, July 2024.