Medicare Advantage and Medicare supplement insurance, or Medigap, are not interchangeable. Medicare Advantage is another way to receive Medicare Part A and Part B coverage through a private plan. Medigap supplements Original Medicare by helping pay certain costs that Original Medicare leaves behind.

Educational note: This is general education, not a recommendation. Medicare Advantage benefits, networks, premiums, and formularies vary by plan and service area, and change from year to year. This article does not make claims about 2027 plans or prices.

The basic difference

With Original Medicare plus Medigap, Medicare remains your primary coverage. You may generally use any doctor or facility that accepts Medicare, although a provider must accept Medicare for Medicare to pay. Medigap helps with certain Medicare-covered cost sharing. You usually consider a separate Part D plan for outpatient prescription drugs.

With Medicare Advantage, you receive Part A and Part B benefits through a Medicare-approved private plan. You continue paying the Part B premium and may also pay a plan premium. The plan sets cost-sharing rules for covered services within federal limits. Many Medicare Advantage plans include Part D drug coverage, but not all plans are identical. Medicare describes the two coverage paths.

You generally cannot buy a Medigap policy to cover cost sharing for a Medicare Advantage plan. If you have Medicare Advantage and want Medigap, you must first return to Original Medicare and confirm whether you have a right to buy a Medigap policy.

Provider access and networks

Original Medicare generally allows nationwide access to participating providers. A Medigap policy does not create a provider network, so the key question is whether the provider accepts Medicare and whether the service is covered.

Medicare Advantage plans may use HMOs, PPOs, or other structures. Each plan’s directory and evidence of coverage explain which providers are in network, how referrals work, and what happens when you use out-of-network care. A PPO may cover some out-of-network care at a higher cost, while an HMO may generally require in-network care except for emergencies and other defined circumstances. Always verify a doctor’s and hospital’s status directly with the plan before enrolling.

Comparing costs fairly

A low or $0 plan premium does not mean that all care is free. With Medicare Advantage, you may pay copayments or coinsurance when you use services, and the plan has a yearly limit on what you pay for covered Part A and Part B services. Premiums, deductibles, cost sharing, and the limit vary by plan.

With Original Medicare and Medigap, you typically pay a monthly Medigap premium in addition to Part B and any Part D premium. Depending on the plan, Medigap can make certain Medicare-covered costs more predictable. It does not cover every expense, and it is not accurate to assume that every Medigap plan has an annual out-of-pocket maximum. Plans K and L have standardized out-of-pocket limits, while other plans have different cost-sharing designs. Use Medicare’s comparison tools for plan-specific details.

The useful comparison is not simply premium versus premium. Compare your likely total cost, including premiums, deductibles, copayments, coinsurance, drug costs, and the cost of services a plan excludes.

Prescription drugs and extra benefits

Medigap policies sold today generally do not include outpatient prescription drug coverage. If you keep Original Medicare and Medigap, review standalone Part D options separately.

Many Medicare Advantage plans include Part D and may offer supplemental benefits such as dental, vision, hearing, transportation, or fitness benefits. These benefits vary in eligibility rules, provider networks, allowances, and limits. Treat them as plan-specific features, not guaranteed benefits across Medicare Advantage.

Travel and continuity of care

Original Medicare and Medigap can be attractive to people who receive care in multiple states, because provider access is generally based on Medicare participation rather than a local plan network. Some Medigap plans include limited emergency foreign travel benefits.

Medicare Advantage coverage is tied to the plan’s service area and rules. Emergency and urgently needed care have federal protections, but routine care while traveling may be subject to the plan’s network and authorization rules. Before enrolling, ask how the plan handles snowbird travel, specialists, hospital systems, and planned treatment away from home.

Switching is not always simple

Medicare has enrollment periods and special rights that govern when you can join, leave, or change plans. The Medicare Advantage Annual Election Period is October 15 through December 7, with changes generally effective January 1. Other periods may apply in specific circumstances.

Leaving Medicare Advantage and returning to Original Medicare does not automatically guarantee Medigap acceptance. You may have a Medigap Open Enrollment Period, a guaranteed issue right, or a trial right, depending on your situation. Before dropping a policy, verify the dates and obtain written confirmation of new coverage. Review Medicare’s Medigap rights and Texas consumer information from the Texas Department of Insurance consumer resources.

Questions to ask before choosing

Are my doctors, hospitals, and specialists in network, and will that change next year?
What will I pay for primary care, specialists, hospital stays, imaging, and outpatient procedures?
Does the plan require referrals or prior authorization?
Are my prescriptions covered, and are my pharmacies preferred?
What is the plan’s yearly limit for covered Part A and Part B services?
If I travel, how are routine, urgent, and emergency services handled?
If I later want Medigap, what guaranteed issue or underwriting rules could apply?

There is no universal winner. The better fit depends on your providers, budget, travel, prescription needs, comfort with networks, and willingness to compare plan details each year.

Before you act

Compare your doctors, prescriptions, travel needs, premiums, and likely out-of-pocket costs using official Medicare tools and plan documents. Ask Medicare, SHIP, or a licensed professional to confirm switching rights before changing coverage.

Medicare Advantage vs. Medigap: How to Compare Your Options