A Medicare HMO is a type of Medicare Advantage plan that requires you to use doctors and hospitals within a specific network, and you must pick a primary care doctor who coordinates your care.

Unlike Original Medicare, which lets you see any doctor who accepts Medicare, an HMO plan restricts your choices to a closed list of providers. You pay a monthly premium (usually lower than other Medicare Advantage plans), and the HMO covers your hospital stays, doctor visits, and prescription drugs all in one plan. The trade-off is that you generally cannot see a specialist without a referral from your primary care doctor, and you cannot go out of network except in emergencies.

HMO stands for Health Maintenance Organization. The insurance company contracts with specific doctors, hospitals, and clinics in your area. When you join an HMO, you are choosing to use only those contracted providers. If you see a doctor outside the network without an emergency, you pay the full cost yourself.

Key Takeaways

  • Medicare HMO plans require you to choose a primary care doctor who must refer you to specialists and coordinate all your care.
  • You can only see doctors and use hospitals in the HMO's network, except in true emergencies, or you pay out of pocket.
  • Monthly premiums for HMO plans are often lower than other Medicare Advantage options, but you may pay copays at each visit.
  • HMO plans include prescription drug coverage (Part D) and often add benefits like dental or vision that Original Medicare does not cover.
  • You must live in the HMO's service area to join, and coverage ends if you move out of that area.

How the Network and Primary Care Doctor Work

When you join a Medicare HMO, your first step is to pick a primary care doctor from the plan's list. This doctor becomes your main point of contact for all non-emergency care. Your primary care doctor manages your overall health, keeps your medical records, and decides whether you need to see a specialist.

If you need to see a cardiologist, rheumatologist, or any other specialist, your primary care doctor must write a referral first. The HMO will not pay for the specialist visit without that referral. This system is designed to keep costs down by preventing unnecessary specialist visits, but it also means you cannot straightforward call a specialist and make an appointment on your own.

The network itself varies by plan and by region. A large HMO in an urban area might have hundreds of doctors and multiple hospitals. A smaller HMO in a rural area might have fewer choices. Before you join, you should check whether your current doctors are in the network. If your doctor is not listed, you will need to switch to someone in the plan or pay out of pocket to keep seeing them.

Costs: Premiums, Copays, and Out-of-Pocket Limits

Medicare HMO plans charge a monthly premium, which is the amount you pay to the insurance company each month to stay enrolled. Many HMO plans have a premium of $0, meaning you pay nothing beyond your regular Medicare Part B premium. Other plans charge $20 to $100 or more per month, depending on the plan and the benefits it includes.

On top of the premium, you pay copays when you use care. A copay is a fixed amount you pay at the time of service — for example, $15 for a doctor visit, $50 for an emergency room visit, or $5 to $10 for a prescription. These copays are usually lower in HMO plans than in other types of Medicare Advantage plans, which is one reason HMOs appeal to people on a tight budget.

Every HMO plan has an out-of-pocket maximum, which is the most you will pay in copays and coinsurance in a calendar year. Once you reach that limit, the plan pays 100 percent of your covered services for the rest of the year. The out-of-pocket maximum varies by plan but is set by Medicare each year. In 2024, the maximum is $7,550 for in-network care in most plans, though this changes annually.

If you receive care outside the network without an emergency, you pay the full cost. The HMO does not count that spending toward your out-of-pocket maximum, and you get no reimbursement.

What Is Covered and What Is Not

Medicare HMO plans cover everything that Original Medicare covers: hospital stays (Part A), doctor visits and outpatient care (Part B), and prescription drugs (Part D). Many HMO plans also add extra benefits that Original Medicare does not cover, such as dental cleanings, vision exams, hearing aids, or fitness programs. These extras vary widely by plan, so you need to check what each plan offers.

What is not covered depends on the specific plan, but common exclusions include cosmetic surgery, weight-loss surgery (unless medically necessary), and most long-term care or nursing home stays. If you need a service, ask your primary care doctor or call the HMO directly to find out whether it is covered before you receive it. Getting an answer in writing protects you if there is a billing dispute later.

Prescription drug coverage is built into every Medicare HMO plan. You do not need to buy a separate Part D plan. The HMO maintains a formulary, which is a list of drugs the plan covers. If your doctor prescribes a drug that is not on the formulary, you can ask the HMO to make an exception, but there is no may provide they will approve it. Some drugs require prior authorization, meaning the HMO must approve them before the pharmacy will fill the prescription.

When You Can Join or Switch Plans

You can join a Medicare HMO during the Annual Enrollment Period, which runs from October 15 to December 7 each year. Coverage begins on January 1 of the following year. If you are newly may be able to access for Medicare (turning 65 or becoming may be able to access due to disability), you have a seven-month Initial Enrollment Period to join without penalty.

If you are already in an HMO and want to switch to a different plan or to Original Medicare, you can do so during the Annual Enrollment Period. You can also switch if you experience a may have access to life event, such as moving out of the plan's service area, losing your current coverage, or getting married. These special circumstances allow you to change plans outside the normal enrollment window.

If you move out of your HMO's service area, your coverage ends on the last day of the month in which you move. You must switch to a different plan or to Original Medicare. This is one of the biggest limitations of HMO plans: they are tied to a specific geographic region, and you cannot take the plan with you if you relocate.

HMO vs. Other Medicare Advantage Plans

Medicare Advantage comes in several types: HMO, PPO (Preferred Provider Organization), and PFFS (Private Fee-for-Service). The main difference is how much freedom you have in choosing doctors and whether you need referrals.

In an HMO, you must use in-network doctors and get referrals for specialists. In a PPO, you can see any doctor without a referral, but you pay less if you use in-network providers. In a PFFS plan, you can see any doctor who accepts the plan's payment rate, and you do not need referrals. PPO and PFFS plans offer more flexibility but usually charge higher premiums and copays than HMO plans.

If you rarely see doctors and want the lowest possible premium, an HMO may save you money. If you have multiple chronic conditions, see specialists regularly, or travel frequently, a PPO or Original Medicare might be a better fit, even if the monthly cost is higher.

Questions to Ask Before You Enroll

Before you join a Medicare HMO, contact the plan directly or visit its website to answer these questions: Are my current doctors in the network? If not, will I be satisfied with the doctors who are? What is the monthly premium, and what are the copays for the services I use most often? What is the out-of-pocket maximum? Does the plan cover the prescription drugs I take? Are there any extra benefits I value, such as dental or vision? What is the process for getting a specialist referral, and how long does it usually take?

You can also call Medicare at 1-800-MEDICARE to ask questions or to request a printed copy of the plan's Summary of Benefits and Coverage. This document lays out exactly what the plan covers and what you will pay.

Frequently Asked Questions

Do I have to use the HMO's doctors, or can I see my own doctor?

You must use doctors in the HMO's network. If your current doctor is not in the network, you can either switch to a network doctor or stay with your doctor and pay the full cost yourself. Before you join, check the plan's website or call to confirm your doctor is listed.

What happens if I need emergency care outside the network?

Emergency care is covered even if you go to an out-of-network hospital or emergency room. The HMO defines what counts as an emergency — typically sudden, severe symptoms that require when ready treatment. Non-emergency care outside the network is not covered, and you pay the full bill.

Can I travel and still use my HMO coverage?

HMO coverage is limited to the plan's service area. If you travel within the United States, you can use emergency services anywhere, but routine care is not covered outside the network. If you travel frequently or spend winters in another state, an HMO may not be the right choice for you.

What if my doctor leaves the HMO network?

If your primary care doctor leaves the network, the HMO will notify you and ask you to choose a new primary care doctor from the remaining network. You have time to make this choice, but you cannot keep seeing your old doctor through the HMO plan once they leave.

Can I switch from an HMO to Original Medicare during the year?

You can switch during the Annual Enrollment Period (October 15 to December 7) or if you have a may have access to life event, such as moving out of the service area. Outside these windows, you are locked into your current plan until the next enrollment period.