Medicare Part B covers outpatient medical services, preventive care, doctor visits, medical supplies, and mental health services. It’s the half of Original Medicare that handles nearly everything outside of hospital inpatient stays (which fall under Part A). In 2025, the standard monthly premium is $185.00, with an annual deductible of $257. After you meet that deductible, you typically pay 20% of the Medicare-approved amount for covered services.
Doctor Visits and Outpatient Care
Part B covers the bulk of what most people think of as “going to the doctor.” That includes office visits with physicians and specialists, outpatient surgeries, lab tests, X-rays, stitches, casts, and diagnostic procedures. If you need a costly outpatient surgical procedure like a total knee replacement, your 20% coinsurance applies to the entire episode of care, including any drugs, lab work, and related services bundled into that procedure.
For most outpatient services, you pay 20% of the Medicare-approved amount after your deductible. If you receive care in a hospital outpatient setting rather than a standalone clinic, you’ll generally owe a separate copayment on top of that.
Preventive Services at No Cost
One of the most valuable features of Part B is its preventive care coverage. You pay nothing for most preventive services as long as your provider accepts Medicare assignment. This includes your yearly “Wellness” visit and a one-time “Welcome to Medicare” visit when you first enroll. Beyond those checkups, Part B covers an extensive list of screenings and vaccines:
- Cancer screenings: mammograms, colonoscopies, lung cancer screenings, cervical and vaginal cancer screenings, prostate cancer screenings, and several types of colorectal tests including stool DNA tests and CT colonography
- Cardiovascular screenings: cholesterol and lipid level tests, plus behavioral therapy for heart disease risk
- Diabetes services: diabetes screenings, self-management training, medical nutrition therapy, and the Medicare Diabetes Prevention Program
- Vaccines: flu shots, COVID-19 vaccines, pneumococcal shots, and hepatitis B shots
- Behavioral health screenings: annual depression screenings, alcohol misuse screenings and counseling, tobacco cessation counseling, and obesity behavioral therapy
- Infectious disease screenings: HIV, hepatitis B, hepatitis C, and sexually transmitted infections, plus pre-exposure prophylaxis (PrEP) for HIV prevention
- Other screenings: bone mass measurements, glaucoma tests, and abdominal aortic aneurysm screenings
The key phrase here is “no cost to you,” but that only holds when your provider accepts assignment. If they don’t, you could owe more. Also, if a screening (like a colonoscopy) turns into a diagnostic or treatment procedure during the visit, cost-sharing rules can change.
Mental Health Coverage
Part B covers outpatient mental health care, including individual and group psychotherapy with doctors or other licensed mental health professionals. Family counseling is also covered when its primary purpose is supporting your treatment. Partial hospitalization programs, which provide intensive psychiatric care without a full inpatient stay, fall under Part B as well.
Your annual depression screening is free. Beyond that, standard cost-sharing applies: after your deductible, you pay 20% of the Medicare-approved amount for therapy and psychiatric visits. If you receive mental health services in a hospital outpatient department rather than a private office, expect an additional copayment.
Durable Medical Equipment
Part B covers medically necessary durable medical equipment (DME) prescribed by your doctor for use in your home. To qualify, the equipment must be durable enough for repeated use, serve a medical purpose, be the kind of thing only useful to someone who is sick or injured, and be expected to last at least three years.
Common covered items include blood sugar monitors (along with test strips, lancets, and control solutions), oxygen equipment and accessories, and walkers. The same 20% coinsurance applies after your deductible. Medicare requires you to get DME from Medicare-enrolled suppliers, so check that your supplier participates before purchasing or renting equipment.
Telehealth Services
Through December 31, 2027, Medicare covers telehealth visits from anywhere in the U.S., including your home. These can be video calls with your provider, brief virtual check-ins lasting 10 minutes or less, or e-visits through an online patient portal. Covered telehealth services include outpatient psychotherapy, depression screenings, diabetes self-management training, cardiac and pulmonary rehabilitation, speech therapy, cognitive assessments, and advance care planning.
You pay the same amount for telehealth as you would for an in-person visit: 20% of the Medicare-approved amount after your deductible.
Ambulance Services
Part B covers ground ambulance transportation when traveling in any other vehicle would endanger your health and you need to reach a hospital, critical access hospital, rural emergency hospital, or skilled nursing facility. Medicare pays for transport to the nearest appropriate facility that can provide the care you need, not necessarily the facility you prefer.
Air ambulance (helicopter or airplane) is covered when you need immediate transport that ground vehicles can’t provide quickly enough. In limited cases, Part B also pays for non-emergency ambulance rides if your doctor provides a written order confirming medical necessity. Someone receiving dialysis for end-stage renal disease, for instance, may qualify for routine ambulance transport to and from their treatment facility.
What Part B Does Not Cover
Several common healthcare needs fall outside Part B. The major exclusions are dental care (cleanings, fillings, extractions, dentures), routine eye exams for glasses, hearing aids and the exams to fit them, long-term care, cosmetic surgery, and massage therapy. Routine physical exams are also not covered, though the annual Wellness visit (which is covered) serves a similar purpose by updating your health risk assessment and creating a prevention plan.
Part B also won’t pay for services from a doctor who has opted out of Medicare, except in emergencies. Many people fill these gaps with supplemental coverage like Medigap plans, Medicare Advantage, or standalone dental and vision policies.
Costs, Premiums, and Late Enrollment Penalties
The 2025 standard monthly premium for Part B is $185.00. Higher-income enrollees pay more based on their tax returns from two years prior. The annual deductible is $257, and after meeting it, your standard coinsurance is 20% of the Medicare-approved amount for most services.
If you don’t sign up for Part B when you’re first eligible and you don’t qualify for a special enrollment period (for example, because you had employer coverage), you’ll face a late enrollment penalty. The penalty adds 10% to your monthly premium for every full 12-month period you could have enrolled but didn’t, and it lasts for as long as you have Part B. Waiting two years past your initial eligibility, for instance, means paying a 20% surcharge on top of the standard premium for the rest of your enrollment.