Part A covers hospital care, Part B covers doctor visits and outpatient services

Medicare Part A pays for inpatient hospital stays, skilled nursing facility care after a hospital stay, hospice care, and some home health services. Medicare Part B pays for doctor visits, outpatient care, preventive services, and medical equipment like wheelchairs or oxygen. Most people get both parts together, though you can have one without the other.

Part A is automatic — you are enrolled when you turn 65 if you have worked and paid Medicare taxes for at least 10 years. Part B requires you to sign up during your enrollment window, and you pay a monthly premium. If you miss the Part B enrollment important date, you may face a permanent penalty on your premium.

Together, Part A and Part B are called Original Medicare. They cover a broad range of care, but they do not cover everything — you will have deductibles, copayments, and coinsurance costs, and neither part covers dental, vision, or hearing aids. Many people add Medigap (supplemental insurance) or Medicare Advantage (Part C) to fill the gaps.

Key Takeaways

  • Part A covers hospital stays and skilled nursing care after hospitalization; Part B covers doctor visits, outpatient services, and preventive care.
  • Part A is automatic at 65 if you have paid Medicare taxes for 10 years; Part B requires you to sign up and you pay a monthly premium.
  • Original Medicare (Part A and B together) has deductibles and coinsurance, and does not cover dental, vision, hearing aids, or long-term custodial care.
  • If you miss your Part B enrollment window, you may owe a permanent penalty increase on your premium for as long as you have Medicare.

What Part A covers and what you pay

Part A covers a hospital stay from the moment you are admitted as an inpatient until you are discharged. In 2024, you pay a one-time deductible of $1,632 per benefit period (the deductible amount changes each year). After you meet the deductible, you pay nothing for days 1–60 of your hospital stay. Days 61–90 cost you $408 per day in coinsurance. If you stay longer than 90 days, you can use your "lifetime reserve days" — 60 additional days covered at $816 per day coinsurance.

Part A also covers up to 100 days in a skilled nursing facility (a facility that provides medical care and rehabilitation, not a long-term care home) if you were hospitalized for at least three days first. You pay nothing for days 1–20. Days 21–100 cost you $204 per day in coinsurance. Part A does not cover custodial care — help with bathing, dressing, or eating — unless it is part of a skilled nursing stay.

Home health services covered by Part A include nursing care, physical therapy, and occupational therapy if a doctor orders them and you are homebound. You pay nothing for home health services. Part A also covers hospice care for people with a terminal illness, with small copayments for drugs and respite care.

What Part B covers and what you pay

Part B covers doctor visits, whether in an office, hospital outpatient department, or urgent care clinic. It also covers preventive services like annual wellness visits, cancer screenings, and vaccinations — these are covered at no cost to you. Diagnostic tests ordered by a doctor, such as blood work or imaging, are covered under Part B.

In 2024, Part B has an annual deductible of $240. After you meet the deductible, you typically pay 20% coinsurance for most services. For example, if a doctor visit costs $100, you pay $20 after the deductible is met. Part B also covers durable medical equipment like walkers, wheelchairs, oxygen, and CPAP machines — you pay 20% coinsurance after the deductible.

Part B does not cover routine dental care, vision exams, eyeglasses, hearing aids, or routine foot care (unless you have diabetes). It also does not cover cosmetic surgery or most weight-loss surgery. If you need these services, you either pay out of pocket or purchase a separate private insurance policy.

How enrollment works and what happens if you miss the important date

You become may be able to access for Medicare at 65. Part A enrollment is automatic if you receive Social Security benefits or Railroad Retirement benefits. If you do not receive benefits, you must contact Social Security to enroll in Part A during your initial enrollment period.

Your Initial Enrollment Period for Part B runs from three months before the month you turn 65 through three months after. If you sign up during this window, your coverage starts the month you turn 65 (or the month after, depending on when you sign up). If you miss this window and do not have other health insurance, you will pay a permanent penalty — an extra 10% on your Part B premium for each 12-month period you were not enrolled. This penalty stays with you for life.

There are exceptions: if you were covered by a group health plan through your job or your spouse's job when you turned 65, you have eight months after that coverage ends to sign up for Part B without penalty. If you are still working and covered by your employer's plan, tell Medicare — you may be able to delay Part B enrollment without penalty.

Original Medicare versus Medicare Advantage and Medigap

Original Medicare (Part A and B) is a fee-for-service plan run by the federal government. You can see any doctor or hospital that accepts Medicare, and there are no networks. However, you are responsible for deductibles, copayments, and coinsurance — costs that can add up if you have a lot of medical care.

Medicare Advantage (Part C) is an alternative to Original Medicare offered by private insurance companies. It includes Part A and B coverage plus usually Part D (prescription drugs) and extra benefits like dental or vision. You typically pay lower out-of-pocket costs, but you must use doctors and hospitals in the plan's network, and you may need prior approval for some services.

Medigap (supplemental insurance) is private insurance you buy to cover the gaps in Original Medicare — deductibles, copayments, and coinsurance. If you have Original Medicare and Medigap, you can see any doctor or hospital that accepts Medicare, and Medigap pays much of what Medicare does not. Medigap premiums vary by plan and location, and you should shop around.

Part D prescription drug coverage

Part D is prescription drug coverage that you add to Original Medicare. It is not automatic — you must sign up during your enrollment period or when you first become may be able to access. Like Part B, if you miss the important date without having other drug coverage, you pay a permanent penalty.

Part D plans are offered by private insurance companies and vary in which drugs they cover and what you pay. Most plans have a deductible, then you pay a copayment or coinsurance for each prescription. If your yearly drug costs reach a certain amount, you enter the "coverage gap" (sometimes called the "donut hole"), where you pay more out of pocket until costs reach a catastrophic level, at which point the plan pays most of the cost.

If you have Medicare Advantage, prescription drug coverage is usually included. If you have Original Medicare and do not want Part D, you do not have to take it — but if you go without drug coverage and later sign up, you will owe the penalty.

When to contact your doctor or Medicare

Contact your doctor if you have questions about whether a service or test is covered under your plan, or if you receive a bill you think Medicare should have paid. Your doctor's office can often check coverage before you come in.

Contact Medicare directly (1-800-MEDICARE) if you need to enroll in Part A or Part B, if you want to change plans, if you have questions about your coverage, or if you received a bill and are not sure why. You can also visit Medicare.gov to review your coverage details, see your claims, and find doctors and hospitals in your area.

Seek when ready care if you have chest pain, difficulty breathing, signs of stroke, or any other emergency — Medicare covers emergency care regardless of whether you pre-approved it. Call 911 or go to the nearest emergency room.

Frequently Asked Questions

Do I have to take Part B when I turn 65?

No, but if you do not sign up during your Initial Enrollment Period and you do not have other health insurance, you will owe a permanent penalty on your Part B premium. If you are still working and covered by your employer's health plan, you can delay Part B without penalty — tell Medicare you are still employed.

Can I have Part A without Part B?

Yes. Some people have Part A only if they rarely see doctors or have other coverage. However, Part B is usually worth the monthly premium because it covers preventive care at no cost and protects you from large bills if you need a doctor visit.

What is the difference between Original Medicare and Medicare Advantage?

Original Medicare is fee-for-service — you can see any doctor or hospital that accepts Medicare. Medicare Advantage is a private plan with a network of doctors and hospitals, usually lower out-of-pocket costs, and extra benefits like dental. You cannot have both at the same time.

How much does Part B cost?

In 2024, the standard Part B premium is $164.90 per month, but it varies based on your income. Higher-income earners pay more. The premium amount changes each year. You can find the current premium on Medicare.gov or by calling 1-800-MEDICARE.

What happens if I do not pay my Part B premium?

If you do not pay your premium, your Part B coverage will end. You can restart it, but you may owe a penalty and there may be a gap in your coverage. Contact Medicare as soon as possible if you are having trouble paying your premium — they may have options to help.