Medicare Part B helps cover medical services like doctors' services, outpatient care, and other medical services that Part A doesn't cover. Part B is optional. Part B helps pay for covered medical services and items when they are medically necessary. Part B also covers some preventive services like exams, lab tests, and screening shots to help prevent, find, or manage a medical problem.
Cost: If you have Part B, you pay a Part B premium each month. Most people will pay the standard premium amount. Social Security will contact some people who have to pay more depending on their income. If you don't sign up for Part B when you are first eligible, you may have to pay a late enrollment penalty.
For more information about enrolling in Medicare, look in your copy of the "Medicare & You" handbook, call Social Security at 1-800-772-1213, or visit your local Social Security office. If you get benefits from the Railroad Retirement Board (RRB), call your local RRB office or 1-800-808-0772.