When you elect to enroll in Medicare Part B, your health plan covers services and supplies that are considered medically necessary to treat a disease or condition. These include a number of services including lab tests, surgeries and doctor visits as well as products such as wheelchairs and walkers.

Health care that can help prevent illnesses or detect conditions at an early stage when treatment is likely to work the best are considered preventive services and are covered by Medicare Part B.

Medicare Part B covers preventive and screening services including the following:

  • Abdominal aortic aneurysm screening
  • Alcohol counseling
  • Bone mass measurements
  • Cardiovascular disease screenings and behavioral therapy
  • Cervical, vaginal, prostate and colorectal cancer screenings
  • Depression screening
  • Diabetes screening and self-management training
  • glaucoma tests
  • HIV screening
  • Mammograms
  • Nutrition therapy services
  • Obesity screening and counseling
  • One-time "Welcome to Medicare" preventive visit
  • Flu, hepatitis B and pneumococcal shots
  • Tobacco cessation counseling
  • Yearly "wellness visit"

In addition to these preventive services, Medicare Part B also covers things like clinical research, ambulance services, inpatient and outpatient mental health services, receiving a second opinion before surgery and a limited number of outpatient prescription drugs.

To receive Medicare Part B coverage, you'll have to pay a monthly premium according to your adjusted gross income on your tax return from two years prior to when you sign up. The majority of beneficiaries pay $104.90 each month and have a yearly deductible of $147.