Medicare Glossary

Medicaid

A joint federal and state program that helps with medical costs for people with limited income and resources. Some people qualify for both Medicare and Medicaid (called "dual eligibles") and may receive extra help with costs.

Medically Necessary

Services or supplies that are needed to diagnose or treat a medical condition and meet accepted standards of medical practice. Medicare only pays for services it considers medically necessary.

Medicare Beneficiary Identifier (MBI)

The unique number printed on your red, white, and blue Medicare card, used to identify you for Medicare claims and services. It replaced Social Security numbers on Medicare cards to help protect against identity theft.

Also known as: MBI, Medicare Number

Medicare Summary Notice (MSN)

A notice you get every 3 months showing all the services or supplies that providers billed to Medicare during that period, what Medicare approved and paid, and what you may owe. It is not a bill but helps you track your Medicare spending.

Also known as: MSN