Medicare Part B (Medical Insurance) Part B covers certain doctors’ services, outpatient care, home health care, durable medical equipment and preventive services (like screenings, shots, and yearly “wellness visits”). Also covered are more specialized services like diabetes testing and care, cancer screenings, mammograms, lab tests, flu shots, and x-rays. Like with Part A, you are typically automatically enrolled in Medicare Part B if you are receiving retirement benefits before age 65 or qualify for Medicare through disability. Medicare Part B doesn’t come free, but paying the premiums is easy because the cost is automatically pulled from your Social Security check each month.