Medicare Part B pays for doctor visits, lab tests, imaging, outpatient surgery, and preventive screenings — but not dental, vision, or hearing care, and not prescriptions filled at a pharmacy.

Part B is medical insurance that covers services and equipment your doctor orders or provides in an office, clinic, or hospital outpatient department. You pay a monthly premium (the amount varies by income), and Medicare covers 80 percent of the approved cost after you meet your annual deductible. You pay the remaining 20 percent, plus any difference between what the doctor charges and what Medicare allows.

Part B does not cover routine dental work, eyeglasses, hearing aids, or prescription drugs you pick up at a pharmacy — those need separate coverage. It also does not cover long-term care in a nursing home, custodial care at home, or most physical therapy beyond what a doctor orders for a specific condition.

Key Takeaways

  • Part B covers office visits with doctors, nurse practitioners, and physician assistants, as well as urgent care and emergency room visits.
  • Lab work, X-rays, ultrasounds, CT scans, and MRI scans are covered when medically necessary, though you may need prior approval for some imaging.
  • Outpatient surgery, dialysis, chemotherapy, and rehabilitation services ordered by your doctor are covered under Part B.
  • Preventive services such as annual wellness visits, cancer screenings, and vaccinations are covered at no cost to you after you meet your deductible.
  • Dental, vision, hearing aids, and prescription medications are not covered by Part B and require separate insurance or out-of-pocket payment.

Doctor Visits and Outpatient Services

Part B covers visits to your primary care doctor, specialists, nurse practitioners, and physician assistants in their offices or in hospital outpatient clinics. It also covers urgent care centers and emergency room visits when you need when ready care. After you pay your annual deductible (which changes each year), Medicare pays 80 percent of the approved amount, and you pay 20 percent.

If your doctor is a participating provider — meaning they accept Medicare's approved amount as full payment — you will not owe anything beyond your 20 percent coinsurance and deductible. If your doctor is a non-participating provider, they can charge up to 15 percent more than Medicare's approved amount, and you will owe that extra charge on top of your coinsurance.

Tests, Imaging, and Diagnostic Services

Part B covers blood tests, urinalysis, and other lab work ordered by your doctor. It also covers imaging services: X-rays, ultrasounds, CT scans, MRI scans, and nuclear medicine scans when medically necessary. You pay 20 percent of the approved cost after your deductible, the same as for a doctor visit.

Some imaging services require prior approval from Medicare before you have the test done. Your doctor's office usually handles this request, but it is worth asking whether approval is needed before you schedule. If you have the test without approval and Medicare denies it, you could owe the full cost.

Outpatient Surgery and Hospital Services

Part B covers surgery performed in a hospital outpatient department or an ambulatory surgery center — places where you go home the same day. It includes anesthesia, the surgeon's fee, and facility costs. You pay 20 percent of the approved amount after your deductible.

If you stay overnight in the hospital, that is covered under Part A (hospital insurance), not Part B. Part B does cover certain hospital outpatient services such as chemotherapy, dialysis, infusions, and rehabilitation therapy ordered by your doctor.

Preventive Care and Screenings at No Cost

Part B covers preventive services at no cost to you — you do not pay anything, even before you meet your deductible. These include an annual wellness visit with your doctor, colorectal cancer screening, mammograms, prostate cancer screening, cardiovascular disease screening, diabetes screening, bone density testing, and vaccinations such as flu, pneumonia, and shingles shots.

To receive these services at no cost, you must go to a participating provider and the service must be ordered as preventive care. If your doctor orders the same test for a different reason — to diagnose or treat a condition rather than screen for one — it may be subject to your deductible and coinsurance.

What Part B Does Not Cover

Routine dental care, including cleanings, fillings, and extractions, is not covered by Part B. Eyeglasses, contact lenses, and routine eye exams are not covered. Hearing aids and hearing exams are not covered. Prescription medications you fill at a pharmacy are not covered by Part B — you need Part D (prescription drug coverage) for those.

Part B also does not cover long-term custodial care at home, such as help with bathing or dressing when that is the only service you need. It does not cover most physical therapy, occupational therapy, or speech therapy unless it is ordered by your doctor to treat a specific condition and is expected to improve your function. Routine foot care, routine eye exams, and most dental work fall outside Part B's scope.

How Much You Pay: Deductible and Coinsurance

Your Part B deductible is a set amount you pay out of pocket each calendar year before Medicare begins to pay its share. Once you meet it, Medicare pays 80 percent of approved costs and you pay 20 percent for most services. The deductible amount changes each year, so check your Medicare materials or call Medicare at 1-800-MEDICARE to find the current year's amount.

Your monthly Part B premium is based on your income from two years prior. If your income was higher in the past, you may pay an income-related premium on top of the standard premium. If your income drops due to retirement or other life changes, you can request a reduction in your premium by contacting Social Security.

Frequently Asked Questions

Does Part B cover physical therapy?

Part B covers physical therapy when your doctor orders it to treat a specific condition — such as therapy after surgery or for a stroke — and when it is expected to improve your function. It does not cover routine exercise classes or wellness programs. You pay 20 percent of the approved cost after your deductible.

Do I have to pay anything for preventive services?

No. Preventive services covered by Part B, such as annual wellness visits, cancer screenings, and vaccinations, are covered at no cost to you when provided by a participating provider. You do not pay a deductible or coinsurance for these services.

What happens if my doctor charges more than Medicare allows?

If your doctor is a participating provider, they accept Medicare's approved amount as full payment and cannot charge you more. If your doctor is non-participating, they can charge up to 15 percent above the approved amount, and you will owe that extra charge in addition to your 20 percent coinsurance.

Does Part B cover prescription drugs?

No. Prescription medications you fill at a pharmacy are covered under Part D (prescription drug coverage), not Part B. You need to enroll in a Part D plan separately, either when you first become may be able to access for Medicare or during the annual enrollment period.

Is emergency room care covered by Part B?

Yes. Emergency room visits are covered by Part B. You pay 20 percent of the approved cost after your deductible, the same as for other Part B services. If you are admitted to the hospital, the hospital stay itself is covered under Part A.