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Medicare parts A,B,C and D explained

Here's what you need to know

This article was last updated on Oct. 7, 2021. 

What is Medicare?

Medicare, the government-sponsored health insurance program for people age 65 and older (and those with certain disabilities), can be a bit confusing to navigate.

Here are the basics:

  • Part A — hospital stays
  • Part B — doctor visits
  • Part C — Medicare Advantage
  • Part D — prescription drug coverage
  • Medicare Supplement (Medigap) — helps with copays, coinsurance and deductibles and covers emergency medical care outside the United States.

Whew — that’s a lot! Let’s break it down so you can easily figure out the combination of coverage that’s right for you.

The different parts of Medicare   You typically enroll in Medicare around your 65th birthday; during the 3 months before, during and 3 months after your 65th birthday.   Original Medicare - Monthly premiums are set by the federal government each year.    Part A, hospital insurance, is free to those who paid Medicare taxes for 10 years, while others will pay a monthly premium. Part A covers hospital stays, skilled nursing facility care, hospice and some home health care.   Part B, medical insurance, has a monthly premium with an annual deductible. Once the deductible is met, you pay 20 percent. Part B covers doctor visits, durable medical equipment, outpatient services and lab tests.   Medicare Advantage, Part C - Once you enroll in Original Medicare, you may combine that coverage through a private insurance company and their network of providers and hospitals.   Medicare Part C may require a low monthly premium ($0-$23), in addition to your Part B premium, plus an out-of-pocket maximum, meaning there's a limit on your annual Medicare expenses.   Medicare Part C plans are approved by Medicare and cover everything Part A and B covers, plus additional benefits, like dental, vision and hearing services and prescription drug coverage.   Prescription drug, Part D - If you enroll in just Original Medicare, you'll likely want to consider prescription drug coverage. Prescription drug coverage has a low monthly premium and is provided through a private insurer. You may also be responsible for a deductible and some out-of-pocket costs. Each plan includes its own list of covered drugs called a formulary.   Medicare Supplement plans - If you enroll in just Original Medicare, you may want assistance with out-of-pocket costs. Medicare Supplement plans cover what's left over after Original Medicare pays your claims, including copays or deductibles. You'll pay a monthly premium that changes based on the level of coverage you select.

What are the different parts of Medicare?

Original Medicare: Part A and B

When you first enroll in Medicare, during your Initial Enrollment Period, you’ll enroll in Part A and possibly Part B, depending on whether you’re still employed.

What does Original Medicare cover?

Medicare Part A covers costs associated with hospital care, like inpatient stays, hospice and skilled nursing. Medicare Part B covers costs for doctor visits, durable medical equipment (like oxygen equipment, a walker or wheelchair and testing strips for people with diabetes), outpatient procedures, lab services and other testing.

While Original Medicare covers the essentials, some products and services aren’t covered, such as prescription drugs, most dental care, eye exams, routine physical exams and hearing aids. For a complete list, visit External Link.

How much does Original Medicare cost?

Costs vary for each part of Original Medicare. You or your spouse likely paid for Medicare Part A already through payroll taxes if you worked for 40 quarters or more. This means that you likely won’t have to pay a premium for Medicare Part A, but you will have to pay a set amount for each hospital admission.

Medicare Part B, however, charges a monthly premium that is set by the federal government External Site each year. You’ll also have an annual deductible. Once you've met your deductible, you'll only be responsible for 20 percent of Medicare-approved costs for most doctor visits.

Medicare Advantage: Part C

Once you enroll in Original Medicare, you may decide to combine that coverage with additional benefits through a private insurance company. Medicare Part C plans, or Medicare Advantage Opens in a new window, are approved by Medicare and cover everything that Original Medicare covers plus additional benefits. Depending on your plan, the cost of services that aren’t considered medically necessary under Medicare may not be covered. You can enroll in a Medicare Advantage plan when you’re first eligible for Medicare or switch Medicare Advantage plans External Link at certain times of the year.

How do Medicare Advantage plans work?

Medicare Advantage combines many Medicare benefits into a single plan, which can make things easier for you. Because they are offered by private insurance companies, they can typically cover more — like dental, vision or hearing services and prescription drug coverage — through their network of health care providers and pharmacies.

What will I pay for Medicare Advantage?

You’ll still have costs associated with Medicare Part B and you may have an additional premium for your Medicare Advantage plan, which varies based on the insurance company you choose. Medicare Advantage plans come with an out-of-pocket maximum — meaning there’s a limit on your annual Medicare expenses.

Feel confident about your Medicare coverage.

Schedule a consultation with one of Wellmark's Medicare experts to learn which Medicare plan option can provide the right level of coverage for you.

Prescription Drug Coverage: Part D

If you choose to enroll just in Original Medicare, or your plan does not offer prescription drug coverage, you’ll likely want to consider Part D Opens in a new window. It’s easiest to purchase Part D from a private insurance company, like Wellmark, at the same time you enroll in a Medicare plan, or add it during the Medicare Annual Enrollment Period.

How does Part D work?

Private insurance companies may offer different Part D plans, each of which have a different list of covered drugs (known as a formulary). You’ll usually pay a monthly premium for this coverage but may also be responsible for a deductible and some out-of-pocket costs.

Medicare Supplement plans

Finally, with all the costs associated with the different parts of Original Medicare, you might want some assistance with out-of-pocket costs. That’s where Medicare Supplement plans come in Opens in a new window (if you haven't chosen to enroll in a Medicare Advantage plan, that is). The best time to enroll in a Medicare Supplement plan is when you’re newly eligible for Medicare, during your seven-month Initial Enrollment Period. You can switch your Medicare Supplement plan at any time, but you may need to answer health questions.

What do Medicare Supplement plans cover?

Medicare Supplement plans are designed to cover what's left over after Original Medicare pays your claim, including any copays or deductibles. Medicare Supplement plans are standardized, meaning a Medicare Supplement plan offered by two different insurers will have the same coverage details. You’ll pay a monthly premium for Medicare Supplement benefits, which changes based on the level of coverage you select.

While Medicare Supplement fills in the gaps left over from Original Medicare coverage, it doesn’t cover prescription drugs or some products and services like vision and dental services, hearing aids and eyeglasses. For a complete list, visit External Link.

Learn more about your Medicare options

No matter when or how you decide to enroll in Medicare Opens New Window, it’s important to understand all the options available to you and the answer to questions like “how many different parts of Medicare are there?”. If you live in Iowa or South Dakota, you can request your free Medicare Get-Ready Guide Opens New WIndow to learn more about the different parts of Medicare, your coverage options and when you're eligible to enroll. You can also call us directly at 800-336-0505.

If you live outside Iowa or South Dakota, visit the Blue Cross Blue Shield Association website External Site or call 888-630-2583 to find a Blue plan near you.