What Does Medicare Part B Cover?

Medicare Part B is the medical insurance side of Medicare. It covers outpatient services, meaning everything that happens outside of a hospital admission. After your $283 annual deductible (2026), Part B pays 80% of the Medicare-approved amount and you pay 20% coinsurance.

Covered Services

Doctor and specialist office visits. Outpatient hospital services and surgery. Clinical lab tests and diagnostic imaging (X-rays, MRIs, CT scans). Mental health services (outpatient therapy and psychiatry). Physical, occupational, and speech therapy. Durable medical equipment like wheelchairs, walkers, hospital beds, and oxygen equipment. Ambulance services when medically necessary. Second surgical opinions. Home health care (limited). Some medications given by a provider in an office or outpatient setting (Part B drugs, including certain cancer drugs and injections).

Preventive Services at No Cost

Part B covers many preventive services at $0 (no deductible, no coinsurance). These include an annual wellness visit, flu and pneumonia shots, COVID vaccines, mammograms, colonoscopies (for people at average risk, every 10 years starting at 45), cardiovascular screenings, diabetes screenings, depression screening, bone density tests, and prostate cancer screening.

What Part B Does Not Cover

Routine dental care (cleanings, fillings, dentures). Routine eye exams for glasses or contacts. Hearing aids and fitting exams. Most prescription drugs you take at home (that's Part D). Long-term care or custodial care. Care outside the United States (with limited exceptions). Cosmetic surgery.

Filling the Gaps

The 20% coinsurance on Part B services has no cap under Original Medicare. For a $50,000 surgery, you'd owe $10,000. That's why many people buy a Medigap supplement (Plan G covers all Part B coinsurance) or choose Medicare Advantage, which caps out-of-pocket spending at $9,250 in-network for 2026.