Medicare Part B covers two broad categories: medically necessary services and preventive care. It pays for doctor visits, outpatient procedures, mental health services, durable medical equipment, ambulance transport, and a long list of preventive screenings at no cost to you. In 2025, the standard monthly premium is $185.00, with an annual deductible of $257.
Doctor Visits and Outpatient Care
Part B is the outpatient side of Original Medicare. It covers visits to doctors, specialists, nurse practitioners, and physician assistants, whether you’re being treated for a chronic condition, getting a diagnosis, or following up after a hospital stay. Outpatient surgeries, diagnostic tests, lab work, and X-rays all fall under Part B as long as they’re considered medically necessary.
After you meet the $257 annual deductible, you typically pay 20% of the Medicare-approved amount for most services. Your doctor or provider covers the rest through Medicare reimbursement.
Preventive Services at No Cost
One of Part B’s biggest benefits is its preventive care coverage. You pay nothing for most preventive services when you see a provider who accepts Medicare assignment. This includes a one-time “Welcome to Medicare” visit within your first 12 months of enrollment and a yearly wellness visit after that, which is essentially a health planning session with your doctor rather than a head-to-toe physical exam.
The list of covered screenings is extensive:
- Cancer screenings: mammograms, colonoscopies, lung cancer screenings with low-dose CT, prostate cancer screenings, and cervical/vaginal cancer screenings
- Cardiovascular screenings: cholesterol and lipid level tests, plus behavioral therapy for heart disease risk
- Diabetes screenings and a full diabetes prevention program
- Mental health: one depression screening per year at a primary care office
- Infectious disease: HIV screenings, hepatitis B and C screenings, sexually transmitted infection screenings and counseling
- Other screenings: bone density measurements, glaucoma tests, abdominal aortic aneurysm screenings, alcohol misuse counseling, obesity behavioral therapy
Part B also covers flu shots, pneumococcal shots, COVID-19 vaccines, and hepatitis B shots at no cost.
Mental Health and Substance Use Services
Part B covers a wide range of outpatient mental health care, including individual and group psychotherapy, psychiatric evaluations, medication management, and family counseling when it supports your treatment. You can receive these services from psychiatrists, clinical psychologists, clinical social workers, nurse practitioners, marriage and family therapists, and licensed mental health counselors.
Coverage also extends to intensive outpatient programs, partial hospitalization, safety planning if you’re at risk of suicide or overdose, and FDA-cleared digital mental health treatment devices. If you visit the emergency department for a behavioral health crisis, Part B covers a follow-up phone call after discharge. Substance use disorder treatment is covered as well, including mental health services you receive as part of that treatment.
Durable Medical Equipment
Part B covers medically necessary equipment prescribed by your doctor for use in your home. To qualify as durable medical equipment, an item must withstand repeated use, serve a medical purpose, be primarily useful to someone who is sick or injured, and be expected to last at least three years.
Covered items include wheelchairs and scooters, walkers, canes, crutches, hospital beds, oxygen equipment and accessories, CPAP machines for sleep apnea, blood sugar monitors with test strips and lancets, infusion pumps, and respiratory assist devices. You typically pay 20% of the Medicare-approved amount after your deductible, though some equipment is rented rather than purchased.
Prescription Drugs Under Part B
Part B doesn’t replace Part D drug coverage, but it does cover a specific subset of medications, mostly drugs that are administered by a healthcare provider or used with medical equipment rather than pills you pick up at a pharmacy.
This includes most injectable and infused drugs given in a doctor’s office or outpatient clinic, drugs delivered through durable medical equipment like nebulizers or infusion pumps, and certain oral medications that have injectable equivalents (some oral cancer drugs and anti-nausea drugs used with chemotherapy fall into this category). Part B also covers injectable osteoporosis drugs, clotting factors for hemophilia, HIV prevention medication, immunosuppressive drugs after a Medicare-covered organ transplant, and IV immune globulin for primary immune deficiency disease administered at home. Tube feeding and IV nutrition are covered when you can’t absorb food normally.
Ambulance Services
Part B covers ground ambulance transport when your medical condition makes any other form of transportation unsafe. Medicare presumes medical necessity when you were in an emergency like an accident or acute illness, were unconscious or in shock, needed oxygen or emergency treatment during transport, showed signs of a stroke or cardiac distress, had an unset fracture, were experiencing severe bleeding, or were bed-confined before and after the trip.
Air ambulance coverage, by helicopter or fixed-wing aircraft, has a higher bar. It’s only covered when ground transport would take too long and endanger your survival, or when the pickup location is inaccessible by road. This comes up most often in remote areas or when a patient needs to reach a specialized hospital quickly.
Telehealth Services
Through December 31, 2027, Medicare covers telehealth visits from anywhere in the U.S., including your home. These can be audio-and-video visits or, in some cases, audio-only phone calls. Covered telehealth services include outpatient psychotherapy, depression screenings, diabetes self-management training, cardiac and pulmonary rehabilitation, cognitive assessments, medical nutrition therapy, speech therapy, and advance care planning. You pay the same 20% coinsurance you’d pay for an in-person visit.
What Part B Does Not Cover
Part B has notable gaps. It does not cover routine dental care, including cleanings, fillings, extractions, or dentures. Eye exams for prescription glasses and hearing aids (along with the fitting exams) are excluded. Long-term custodial care, whether in a nursing home or at home, is not covered. Cosmetic surgery, massage therapy, and routine physical exams outside the yearly wellness visit are also excluded.
If your provider has opted out of Medicare entirely, Part B won’t pay for their services except in emergencies. And concierge or boutique medicine fees, where you pay a retainer for enhanced access to a practice, are not reimbursed. Many of these gaps can be partially filled through supplemental Medigap policies, Medicare Advantage plans, or standalone dental and vision plans.