Part B is the part of Medicare that covers outpatient care. Outpatient services include doctor’s visits, preventive care, durable medical equipment (DME), laboratory tests, x-rays, and ambulance services.

Whether or not someone who is eligible for Medicare should take Part B depends on how the person receives his or her insurance benefits. Medicare can be either primary or secondary to other insurance. If someone does not enroll into Medicare Part B when they should, even if they believe they are covered, they could pay penalties or have no insurance coverage at all.

Use the tool below to get more information about Part B enrollment rules. Before you make a decision about Medicare Part B, you should always contact Social Security by dialing 800-772-1213 or visiting your local Social Security office. When you contact Social Security, use this list of questions to gather the correct information.