Quick answer
An HMO (health maintenance organization) is a health plan that covers care only from doctors and hospitals in its network, except in emergencies. You usually pick a primary care doctor who coordinates your care and gives referrals to specialists. In exchange for those limits, HMOs tend to have lower premiums and simpler costs than PPO plans.
Key takeaways
- HMOs don’t pay for non-emergency care outside the network, so check that your doctors are included.
- Most HMOs require a primary care doctor and referrals to see specialists. EPOs are similar but usually skip referrals; see what is an EPO plan.
- Emergency care is covered anywhere, at in-network cost-sharing.
- Premiums and out-of-pocket costs are often lower than for PPO plans.
- HMOs are common on the ACA marketplace, where they make up a large share of the plans sold.
On this page
How an HMO works
When you join an HMO, you choose a primary care doctor from the plan’s network. That doctor handles your routine care and refers you to specialists, labs and hospitals in the network when you need them. Some HMOs let you see certain specialists, like OB-GYNs, without a referral.
If you go outside the network for care that isn’t an emergency, you’ll usually pay the full bill yourself. Many HMOs also require prior approval for tests like MRIs or for hospital stays.
Advantages
- Lower cost. Premiums, deductibles and copays are often lower than PPOs with similar coverage.
- Predictable bills. Many HMOs use flat copays for visits and drugs.
- Coordinated care. Your primary care doctor keeps track of your care and can help avoid duplicate tests.
Disadvantages
- Limited choice. You’re restricted to the network, which can be small.
- Referrals. Seeing a specialist often takes an extra step.
- Little coverage away from home. Outside your service area, most HMOs cover only emergencies and sometimes urgent care, which matters for students and frequent travelers. See is health insurance required for college students.
Who an HMO fits
An HMO works well if your doctors are in its network, you’re comfortable getting referrals, and you want to keep costs down. It’s often a good match for a single person on a budget or a family whose doctors all belong to the same health system. It’s a harder fit if you want to keep a specific out-of-network doctor or you spend a lot of time in another state.
Finding a good HMO
- Search the plan’s provider directory for your doctors, and call their offices to confirm.
- Check that your medications are on the drug list.
- Look at the plan’s quality rating on HealthCare.gov, and compare a few insurers.
- If you qualify for a premium tax credit, compare HMOs at different metal levels after the credit.
For more ways to save, see health insurance discounts. To compare HMOs with other plan types, read what is better, a PPO or an HMO and health insurance coverage types.
See HMO and other plans available near you: compare quotes by ZIP code.
Frequently asked questions
Does an HMO cover emergencies out of network?
Yes. ACA plans, including HMOs, must cover emergency care at any hospital without prior approval, at your in-network cost-sharing.
Can I see a specialist without a referral in an HMO?
Usually not, though some HMOs allow direct access to certain specialists, like OB-GYNs. Check your plan’s rules.
What’s the difference between an HMO and an EPO?
Both generally cover only in-network care. EPOs usually don’t require referrals to see specialists.
Are HMOs cheaper than PPOs?
Usually, but not always. Compare the premium, deductible and out-of-pocket maximum for the specific plans available to you.
Sources
This article is general information, not insurance advice. Rules differ by plan, so check your plan documents or ask the insurer. Last reviewed September 2026.