What Medicare Part B Covers and What It Doesn't

Medicare Part B covers doctor visits, outpatient care, and some preventive services

Medicare Part B is the medical insurance piece of Original Medicare. It pays for visits to doctors and specialists, lab tests, imaging like X-rays and ultrasounds, outpatient surgery, emergency room visits, and ambulance transport. It also covers certain preventive care at no cost to you — annual wellness visits, cancer screenings, vaccines — and some equipment like wheelchairs or oxygen if your doctor orders it.

Part B does not cover hospital stays (that is Part A), prescription drugs taken at home (that is Part D), long-term care, dental work, vision exams, or hearing aids. It also does not cover services deemed not medically necessary, experimental treatments, or care from providers who do not accept Medicare.

You pay a monthly premium for Part B — the amount depends on your income and when you first became may be able to access. You also pay a yearly deductible before Part B starts paying, and then you pay 20 percent of the cost for most services after that.

Key Takeaways

Part B covers doctor office visits, specialist consultations, lab work, imaging, and outpatient procedures, but not hospital inpatient stays or prescription drugs.
Preventive services like annual wellness visits, cancer screenings, and certain vaccines are covered at no cost to you under Part B.
You pay a monthly premium for Part B, a yearly deductible, and then 20 percent coinsurance for most services after the deductible is met.
Part B only pays providers who accept Medicare; if you see an out-of-network provider, you may owe the full bill.

Doctor visits and specialist care

Part B covers visits to your primary care doctor, cardiologists, orthopedists, neurologists, and other specialists. It pays for the office visit itself, any tests the doctor orders during that visit, and consultations. You will pay your deductible first (currently $240 per year, though this amount can change), and then Part B pays 80 percent of the approved amount while you pay 20 percent.

The key word is "approved amount." Medicare sets a fee schedule for each service in each region. If your doctor accepts Medicare assignment, they agree to bill only the approved amount and cannot charge you more. If your doctor does not accept assignment, they can charge you up to 15 percent above the approved amount, and you are responsible for the difference.

To find out whether a doctor accepts Medicare, ask before your first visit or check the Medicare provider search tool on Medicare.gov. Telehealth visits with doctors who accept Medicare are also covered under Part B, with the same cost-sharing rules as in-person visits.

Lab tests, imaging, and diagnostic procedures

Part B covers blood tests, urinalysis, and other lab work ordered by your doctor. It also covers imaging — X-rays, CT scans, MRI, ultrasounds — and diagnostic procedures like EKGs, stress tests, and colonoscopies. Once you have met your deductible, you pay 20 percent of the approved amount for these services.

Some imaging and tests require your doctor to get prior approval from Medicare before the service is done. If your doctor does not get approval and Medicare later decides the test was not medically necessary, you may be responsible for the full cost. Your doctor's office should handle prior authorization requests, but it is worth asking whether approval is needed before you go in for the procedure.

Preventive care at no cost

Part B covers certain preventive services with no deductible and no coinsurance — you pay nothing. These include an annual wellness visit with your doctor, colorectal cancer screening, breast cancer screening (mammogram), cervical cancer screening, prostate cancer screening, cardiovascular screening, diabetes screening, bone density screening, and vaccines like the flu shot, pneumonia vaccine, and shingles vaccine.

To receive these services at no cost, you must use a doctor or facility that accepts Medicare assignment. If you go to an out-of-network provider, you may be charged the full cost. The preventive services covered can change, so check Medicare.gov or ask your doctor which screenings are covered at no cost for you.

Outpatient surgery and emergency care

Part B covers surgery performed in an outpatient setting — meaning you go home the same day rather than staying overnight in the hospital. This includes procedures done in a hospital outpatient department, an ambulatory surgery center, or a doctor's office. You pay your deductible and then 20 percent coinsurance for outpatient surgery.

Emergency room visits are also covered under Part B. Part B pays for the emergency department visit itself, any tests and imaging done in the ER, and any procedures. If you are admitted to the hospital from the ER, your hospital stay is covered under Part A instead. Ambulance transport to a hospital or other facility is covered if it is medically necessary.

Durable medical equipment and supplies

Part B covers durable medical equipment — items that are ordered by your doctor, used repeatedly, and expected to last at least three years. This includes wheelchairs, walkers, canes, hospital beds, oxygen equipment, CPAP machines, and diabetic supplies like test strips and lancets. You pay 20 percent of the approved amount after your deductible.

The equipment must be ordered by your doctor and must be medically necessary for your condition. You cannot straightforward buy equipment and ask Medicare to reimburse you; the order must come from a doctor first. Some equipment requires prior authorization from Medicare before you obtain it.

What Part B does not cover

Part B does not cover hospital inpatient stays — that is Part A's role. It does not cover prescription medications you take at home; those are covered under Part D. Part B also does not cover dental care, routine eye exams, eyeglasses, hearing aids, or routine hearing exams. Cosmetic surgery is not covered unless it is medically necessary to repair an injury or birth defect.

Part B does not cover long-term care in a nursing home or assisted living facility, custodial care (help with bathing, dressing, eating), or care that is not ordered by a doctor. It also does not cover services from providers who do not accept Medicare, though you may still receive care from them — you just pay the full bill yourself.

How much you pay for Part B

Your Part B premium depends on your income. Most people pay a standard monthly premium, but if your income is above a certain threshold, you pay a higher amount called an Income-Related Monthly Adjustment Amount (IRMAA). The income limits and premium amounts change each year.

In addition to the premium, you pay a yearly deductible before Part B starts paying for services. Once you meet the deductible, you typically pay 20 percent coinsurance for most services. Some preventive services have no deductible and no coinsurance. If you have a Medigap or Medicare Advantage plan, your out-of-pocket costs may be different.

Frequently Asked Questions

Does Part B cover my doctor's office visit if I have not met my deductible yet?

Part B will not pay anything toward your visit until you have met your yearly deductible. Once the deductible is met, Part B pays 80 percent of the approved amount and you pay 20 percent. If your doctor accepts Medicare assignment, you will not be charged more than the approved amount.

What happens if I see a doctor who does not accept Medicare?

If your doctor does not accept Medicare assignment, they can charge you up to 15 percent more than Medicare's approved amount. You are responsible for paying the difference. It is worth checking whether your doctor accepts Medicare before scheduling an appointment.

Are mental health visits covered under Part B?

Yes, Part B covers visits to psychiatrists, psychologists, and clinical social workers for mental health treatment. You pay the same deductible and 20 percent coinsurance as you would for other doctor visits. Some preventive mental health screenings are also covered at no cost.

Does Part B cover physical therapy?

Yes, Part B covers physical therapy, occupational therapy, and speech-language pathology when ordered by your doctor for a medical condition. You pay 20 percent coinsurance after your deductible. There are limits on the number of visits covered per year, though your doctor can request an exception if medically necessary.

If I skip Part B when I first become may be able to access, can I sign up later?

You can sign up for Part B later, but you may face a permanent penalty on your premium if you do not enroll when you are first may be able to access. The penalty is 10 percent of the standard premium for each year you delayed. Talk to Social Security or Medicare before declining Part B to understand the consequences.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.