The alphabet soup of Medicare — multiple parts and plans, starting with A all the way through N — can be bewildering, especially for those who are newly eligible for Medicare.
In this guide, we break down each part of Medicare to help you find the best health insurance fit for your needs.
Medicare Basics
Medicare is the government health insurance program for those age 65 and older, certain younger beneficiaries with specific disabilities and those with end-stage renal disease or amyotrophic lateral sclerosis (also known as Lou Gehrig’s disease). Medicare is split into four main parts:
— Part A (inpatient care)
— Part B (outpatient care)
— Part C (also known as Medicare Advantage)
— Part D (prescription drug coverage)
What Does Medicare Part A Cover?
Medicare Part A pays for an array of services, including:
— Hospice care
— Hospital stays
— Skilled nursing facility stays
— Short-term home health care
[READ What to Do When Medicare Stops Paying for Skilled Nursing Care]
Medicare Part A Costs
Most people don’t pay a monthly plan premium for Medicare Part A. However, if you have not paid into Medicare through taxes long enough to be eligible for a $0 Part A premium, the rate to buy in is $311 or $565 a month in 2026, depending on how long you or your spouse paid Medicare taxes.
The annual inpatient hospital deductible for Medicaid Part A is $,1,736 in 2026. That’s the amount you’ll have to pay before coverage kicks in. This deductible is also applied each time you access your Part A benefits, during what’s known as a “benefit period.” There is no limit to the number of benefit periods you can have in a year, so you may pay the deductible more than once in a single year.
From hospital days one through 60, you will not have to pay a copayment. From days 61 through 90 in 2026, however, you will be charged a $434 copayment each day. Starting on day 91, the copay increases to $868 per day. The days after day 91 are referred to as “lifetime reserve days.” Each Medicare beneficiary has a total of 60 lifetime reserve days. Once they are exhausted, you will be responsible for the cost of your hospitalization unless you have purchased a separate Medigap plan (more on this below).
Members will also need to pay skilled nursing facility copays and hospice coinsurance, should they need these services. However, there is no cost for beneficiaries who qualify for home health care.
What Does Medicare Part B Cover?
Medicare Part B covers:
— Ambulance services, including ground transportation, airplane or helicopter rides for medically necessary emergency services
— Durable medical equipment, including canes, walkers, wheelchairs, hospital beds, pressure mattresses, prostheses, orthotics and other health care devices and products
— Visits to the doctor’s office for outpatient services and certain hospital inpatient services
— Diabetic medical equipment, such as insulin pumps that you can use at home
— Physical therapy, if your doctor or another health care provider certifies you need it
— Occupational therapy, also if your doctor or other health care provider certifies you need it
— Preventive services, such as vaccines to prevent illnesses like the flu or screening tests to detect illness at an early stage when treatment is likely to work best. Preventive services are fully covered if you get them from a provider that accepts Medicare.
— Mental health services, including outpatient and partial hospitalization services. Inpatient mental health care is covered under Part A and is limited to 190 days over your lifetime.
[READ: Does Medicare Cover Medical Equipment?]
Medicare Part B Costs
The monthly plan premium for Medicare Part B for most people is $202.90 in 2026, up from $185 in 2025. The monthly plan premium is income-based, so if your modified adjusted gross income was more than $109,000 in 2024 (if you filed individually) or more than $212,000 if you were married and filed jointly, your 2026 premium may be higher, according to the Centers for Medicare & Medicaid Services. In that case, you could pay an IRMAA (income-related monthly adjustment amount).
The annual deductible for Medicare Part B in 2026 is $283.
While enrolling in Medicare Part B is voluntary, there is a lifetime penalty for not enrolling in Part B in a timely fashion. For each year you could have signed up for Part B but didn’t, you’ll pay an extra 10% of the standard Part B premium for the current year. The penalty is added to your monthly plan premium. Remember that the penalty only applies if you don’t have other insurance (such as an employer-sponsored policy) covering what would be covered by Part B.
Medicare provides this example: Individuals who waited a full two years to sign up for Part B and didn’t qualify for a special enrollment period will have to pay a 20% late enrollment penalty, 10% for each full 12-month period they could have signed up. That would be on top of the standard monthly plan premium.
Another important thing to know: You need Medicare parts A and B (also known as original Medicare) to get a private Medigap policy, also called Medicare supplemental insurance. Such policies help pay for costs not covered by original Medicare, such as copays for visits to the doctor and deductibles. A separate plan premium is paid to a private Medicare-approved insurance company for this coverage.
[READ: Medicare vs. Medicare Advantage: How to Choose.]
What Does Medicare Part C Cover?
Medicare Advantage, also known as Medicare Part C, refers to plans offered through Medicare-approved private insurance companies.
“When you sign up for them, your original Medicare parts A and B benefits are administered through the insurance company you chose, rather than directly through the government,” explains Bob Rees, chief sales officer with eHealth Inc., a health insurance broker and online resource provider headquartered in Santa Clara, California.
Medicare Advantage plans must cover the same services as original Medicare, and they often include prescription drug coverage.
In many ways, these plans are similar to individual health insurance policies provided by employers or available on the individual insurance market. They have different monthly plan premiums, copays, provider networks and out-of-pocket limits. Some plans with no or lower plan premiums might have higher copays or coinsurance, higher out-of-pocket limits and smaller networks of providers. You may also have to pay more for prescription medication coverage.
Regardless of whether the Medicare Advantage plan has a $0 premium, all beneficiaries must pay the monthly Part B premium.
[READ: How Much Does Medicare Pay for a Hospital Stay?]
Pros and Cons of Medicare Advantage Plans
Medicare Advantage plans may offer “a variety of benefits that go beyond what’s typically available with Medicare coverage,” Rees says.
These benefits can include:
— Gym memberships
— Medical transportation
— Vision, dental and hearing care
— Over-the-counter drugs
[SEE: Medicare Grocery Allowance: What It Is and How to Get It]
While bundling all the various elements of health insurance into a single plan can seem more convenient, and some of the extras can be very attractive, “there are trade-offs,” says Ari Parker, co-founder and head Medicare advisor at Chapter, a nationwide service that helps people shop for Medicare plans.
Some of those trade-offs include:
— A more limited network of doctors and hospitals to select from
— A requirement for beneficiaries to obtain referrals and prior authorizations before receiving care or pharmacy benefits
“Whether a Medicare Advantage plan is right for you will depend on your doctors, your drugs, your cost sensitivity and lifestyle priorities,” Parker says. “It’s important to shop across all plan options because there are hundreds of health insurance companies offering thousands of plans nationwide. Your options vary county by county across the country.”
What Does Medicare Part D Cover?
Medicare Part D is prescription drug coverage. You must be enrolled in Part A and/or Part B to get Medicare prescription drug coverage, says Salama Freed, an assistant professor with the Milken Institute School of Public Health at George Washington University in Washington, D.C.
Under Part D, there are limits on which prescription drugs are covered and how much you pay out of pocket for brand-name and generic prescription drugs. In 2026, there is a $2,100 cap on your yearly Part D out of pocket costs. The Part D prescription drug deductible is $615, up from $590 in 2025. And the base Part D plan total monthly premium is $38.99 in 2026, an increase from $38.31 in 2025.
The costs of prescription drugs depend on an array of factors, including:
— The prescriptions you take and whether they are brand-name or generic
— Whether the medications you are prescribed are on your plan’s list of covered medications — referred to as the “formulary”
— What “tier” the prescription drug is in. Medicare prescription drug coverage typically puts prescription drugs in different levels or tiers. Prescription drugs in lower tiers generally cost less than medications in higher tiers.
— Whether you’ve met your annual deductible
— Which pharmacy you use and whether or not it’s in your network
[What Is the Medicare Prescription Payment Plan?]
Medicare Supplement Plans A Through N
Original Medicare can leave you with significant out-of-pocket costs and gaps in coverage. That’s where Medicare supplemental plans come in, Rees says. These insurance plans may be referred to by various letters of the alphabet.
Currently, there are 10 Medigap plans available: A, B, C, D, F, G, K, L, M and N.
However, plans C and F are not available to those who became eligible for Medicare on or after January 1, 2020. For those individuals, the most comparable plans are D and G, which have nearly identical benefits. Some other Medigap plans — H, I and J — have been discontinued for new enrollees but may still be available under certain circumstances. Medicare supplement plan E was discontinued in 2010 for new enrollees, but people who were previously enrolled are able to keep this plan.
Let’s take a closer look at two of the most popular plans.
Medicare Plan F
Plan F is only available to people who turned 65 or qualified for Medicare before January 1, 2020. Access to this plan for those who became eligible for Medicare later was blocked by the 2015 passage of the Medicare Access and CHIP Reauthorization Act, or MACRA.
As with other Medigap plans, Medicare Plan F covers gaps in original Medicare. Coverage benefits include:
— Coinsurance and hospital costs up to an additional 365 days after you’ve exhausted your Medicare benefits
— Deductibles for parts A and B
— Part B coinsurance or copayments
— Part B excess charge
— Blood transfusions
— Skilled nursing facility care coinsurance
— Hospice care coinsurance or copayment
— Coverage for some health care costs incurred while traveling overseas
Medicare Plan G
Medicare Plan G is similar to Plan F, but it excludes the Part B deductible coverage. Plan G has all of the other benefits (as listed above) as Plan F.
What Isn’t Covered by Medicare?
everything. You’ll need to read the fine print of any policy, but generally, you may not find coverage for:
— Long-term care and assisted living costs
— Long-term hospitalization
— Health care costs for spouses and dependents
— Cosmetic surgery
— Nonmedically necessary foot care
Talking with an expert can help you sift through all the options and find the right mix of coverage for your situation.
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Understanding Parts of Medicare: A Through N Explained originally appeared on usnews.com
Update 12/10/25: This story was previously published at an earlier date and has been updated with new information.