HMO — Health Maintenance Organization

Definition. A Medicare Advantage plan that covers care from its network of providers. Out-of-network care usually isn't covered except in emergencies and a few other cases, and most HMOs ask you to choose a primary care doctor.

What it means

• Network: you use the plan's doctors, hospitals and pharmacies. If you see an out-of-network provider for routine care, you may have to pay the full cost.
• Exceptions: emergency care, urgently needed care, and out-of-area dialysis are covered outside the network.
• Primary care doctor and referrals: many HMOs ask you to choose a primary care doctor and get a referral before seeing a specialist.
• Point-of-service (HMO-POS): some HMOs let you get certain services out of network, usually at a higher cost.
• Drug coverage: most include Part D drug coverage.

Medicare Advantage plans may offer extra benefits such as dental, vision, hearing or fitness. Extra benefits vary by plan and county, may have limits and costs, and not every plan offers them. Check a plan's Summary of Benefits or Evidence of Coverage.

Before you join, check that your doctors, hospital and pharmacy are in the network and that your drugs are on the plan's list. Networks can change during the year.

In Oregon

Medicare Advantage choices in Oregon depend on your county. For 2027 there is no Medicare Advantage plan open to everyone in Grant, Harney, Lake, Umatilla and Union counties, and only a special needs plan in Curry County. If you live part of the year somewhere else, an HMO network built around your Oregon county may not cover routine care there. See your county on the county pages.