Medicare Advantage (MA)
Medicare Advantage (MA), also called Medicare Part C, is the way people with Medicare can get their benefits through a private health plan approved by CMS, instead of Original Medicare. MA plans use provider networks and must publish provider directories.
How is Medicare Advantage different from Original Medicare?
With Original Medicare, people can see any provider who accepts Medicare. With Medicare Advantage, a private plan, usually an HMO or PPO, covers their care through its own network, often with extra benefits. Using providers outside the network can cost more or not be covered.
Why do provider directories matter so much in MA?
Members choose and use their plan based on which doctors are in its network. CMS sets network adequacy standards for MA plans, has reviewed the accuracy of MA directories, and from 2026 shows MA directory data in Medicare Plan Finder.
What rules apply?
Network adequacy is set in 42 CFR 422.116 and disclosure rules in 42 CFR 422.111. The REAL Health Providers Act, enacted in 2026, adds 90-day verification, five-day removal and a yearly, public accuracy score for MA directories from plan year 2028.