An HMO (Health Maintenance Organization) Medicare Advantage plan typically requires you to use doctors and hospitals within the plan’s provider network and often requires referrals to see specialists. Out-of-network care is usually not covered except in emergencies.
A PPO (Preferred Provider Organization) Medicare Advantage plan offers more flexibility by allowing you to see out-of-network providers, usually at a higher cost. PPO plans typically do not require referrals for specialists. The choice between an HMO and PPO depends on how important provider flexibility and referral requirements are to you.

