Medicare has two main parts that work together and cover different types of medical care. Medicare Part A covers hospital care and services provided in an inpatient hospital setting, while Medicare Part B covers outpatient care, such as doctor visits.
The Centers for Medicare & Medicaid Services provides two aspects of healthcare coverage: Medicare Part A and Medicare Part B.
Part A provides hospital coverage, while Part B covers doctor’s visits and other aspects of outpatient medical care. These plans aren’t competitors but complement each other, providing both outpatient and inpatient health coverage.
Medicare Part A covers several aspects of healthcare that may include the following:
- short-term care in a skilled nursing facility
- limited home healthcare
- hospice care
- inpatient care at a hospital
For this reason, people often call Medicare Part A hospital coverage.
Eligibility
For Medicare Part A eligibility, you must meet one of the following criteria:
- be age 65 or older
- have a disability as determined by a doctor and receive Social Security benefits for at least 24 months
- have end stage renal disease
- have amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease
Whether or not you receive Part A without a premium depends on your (or your spouse’s) work history.
Costs
Most people who qualify for Medicare do not pay for Part A. This is true if you or your spouse worked for at least 40 quarters (approximately 10 years) paying Medicare taxes.
Even if you didn’t work for 40 quarters, you can still pay a monthly premium for Medicare Part A.
Medicare Part A premium in 2025
In addition to the premium costs (which are $0 for many people), there are other costs in terms of a deductible (what you must pay before Medicare pays) and coinsurance (you pay a portion, and Medicare pays a portion). For 2025, these expenses include:
| Quarters worked and paid Medicare taxes | Premium |
|---|---|
| 40+ quarters | $0 |
| 30–39 quarters | $285 |
| < 30 quarters | $518 |
Medicare Part A hospitalization costs
Inpatient hospitalization days 91 and higher are considered lifetime reserve days. You receive 60 lifetime reserve days to use over the course of your life. If you go beyond these days, you are responsible for all costs after day 91.
A benefit period begins when you are an inpatient and ends when you have not received inpatient care for 60 days in a row.
Here is what you’ll pay in Part A hospitalization coinsurance costs in 2025:
| Time period | Cost |
|---|---|
| deductible for each benefit period | $1,676 |
| inpatient days 1–60 | $0 |
| inpatient days 61–90 | $419 per day |
| inpatient days 91+ | $838 per day |
Other things to know
When you need help in the hospital, Medicare reimbursement often depends on whether the doctor declares you as an inpatient or “under observation.” If you aren’t officially admitted to the hospital, Medicare Part A won’t cover the service (although Medicare Part B might).
There are also aspects of hospital care that Medicare Part A does not cover. These include the first 3 pints of blood, private nursing care, and a private room. Medicare Part A pays for a semiprivate room, but if private rooms are all your hospital offers, Medicare will usually reimburse them.
Medicare Part B covers doctors’ visits, outpatient therapy, durable medical equipment, and, in some cases, prescription medications. Some people also call it “medical insurance.”
Eligibility
For Medicare Part B eligibility, you must be age 65 or older and a U.S. citizen. Those who have legally and permanently resided in the United States for at least 5 years in a row can also qualify for Medicare Part B.
Costs
The cost for Part B depends on when you enrolled in Medicare and your income level. If you enrolled in Medicare during the open enrollment period and your income did not exceed $103,000 as an individual or $206,000 as a couple filing jointly in 2022, you’ll pay $185 a month for your Medicare Part B premium in 2025.
That said, your premium will increase depending on your income bracket and whether you file taxes independently or jointly.
If you receive benefits from Social Security, the Railroad Retirement Board, or the Office of Personnel Management, these organizations will deduct the Medicare deductible before sending you your benefits.
The annual deductible for 2025 is $257. If you do not sign up for Medicare Part B in your enrollment period (usually right around when you turn age 65), you may have to pay a late enrollment penalty on a monthly basis.
Once you meet your deductible for Medicare Part B, you will usually pay 20% of a Medicare-approved service amount, while Medicare will pay the remaining 80%. If the health provider does not accept the Medicare-approved amount for a service, you may have to pay more.
Other things to know
It’s possible that you could be an inpatient in the hospital and have both Medicare Part A and Part B pay for aspects of your stay.
For example, some of the doctors or specialists who see you in the hospital may be reimbursed through Medicare Part B. However, Medicare Part A will cover the cost of your stay and costs related to medically necessary surgery.
Below, you’ll find a table that provides an overview of the main differences between Part A and Part B:
| Part A | Part B | |
|---|---|---|
| Coverage | hospital and other inpatient services (surgeries, limited skilled nursing facility stays, hospice care, etc.) | outpatient medical services (preventative care, doctor’s appointments, therapy services, medical equipment, etc.) |
| Eligibility | age 65 or older, receive disability from Social Security for 24 months, or have a diagnosis of ESRD or ALS | age 65 or older and U.S. citizen or legally qualifying U.S. residency |
| Costs in 2025 | most pay no monthly premium, $1,676 deductible per benefit period, daily coinsurance for stays over 60 days | $185 monthly premium for most people, $257 annual deductible, 20% coinsurance on covered services and items |
If you or a loved one will be enrolling in Medicare soon (or switching plans), don’t miss these important deadlines:
- Initial enrollment period: the 3 months before your 65 birthday, the month of your birthday, and 3 months after your 65 birthday
- General enrollment: January 1 through March 31 for Medicare Part B if you did not sign up during your initial enrollment period
- Open enrollment: October 15 through December 7 for Medicare Advantage and Part D prescription drug plans enrollment or changes
Why would someone have Medicare Part B only?
People who qualify for Medicare will be enrolled in both Part A and B. You can’t drop it if you don’t pay a premium for Part A. However, if you do pay a premium for Part A, you could, in theory, drop it and replace it with a marketplace insurance plan instead, remaining enrolled in Part B only.
Is Medicare Part B free at age 65?
Although you qualify for Part B when you reach the age of 64, it isn’t entirely free. For full coverage, you must pay a monthly premium and meet a deductible.
What do Medicare Part A and B not pay for?
Original Medicare (Parts A and B) doesn’t cover certain vision, hearing, and dental services. But, Medicare Advantage plans (Part C) may cover some of these services.
Learn more: 10 healthcare services Medicare doesn’t cover
Medicare Part A and Medicare Part B are two parts of original Medicare that together help cover most of your healthcare needs by helping pay for hospital and medical costs.
Enrolling in these plans in a timely fashion (3 months before to 3 months after your 65th birthday) is vital to keeping the costs low.
Medicare plan options and costs are subject to change each year.