Medicare Advantage vs. Medicare Supplement, in Plain English

Once you have Original Medicare (Parts A and B), you have a choice to make about the gaps it leaves behind. There are two ways to fill them, and they work very differently. Almost everything else — your cost, your choice of doctors, the paperwork — flows from that one fork in the road.

The two paths, side by side

• Medicare Advantage (Part C). A private plan that bundles your Part A, Part B, and usually Part D into one package, often with extras like dental and vision. You trade a low premium for a provider network and plan-set copays.
• Medicare Supplement (Medigap). Sits on top of Original Medicare and pays the gaps it leaves — the deductibles and the 20% coinsurance. You pay a higher monthly premium for predictable costs and the freedom to use any provider in the country that takes Medicare, and you add a separate Part D plan for drugs.

Medicare Advantage — the trade-offs

• Lower premium, sometimes $0. You still pay your Part B premium, but the plan premium itself is often low.
• Extra benefits. Many plans include dental, vision, hearing, and gym memberships that Original Medicare doesn’t cover.
• Networks and referrals. You generally use the plan’s network of doctors and hospitals and may need referrals; coverage outside the network is limited.
• Costs can shift each year. Copays, the drug formulary, and the network can change every January. There’s an annual in-network out-of-pocket maximum — as high as $9,250 in 2026, though most plans set theirs lower.

Medicare Supplement — the trade-offs

• Any doctor that takes Medicare. No networks and no referrals — which matters if you travel or split the year between states.
• Predictable costs. Depending on the plan letter, your out-of-pocket can be close to nothing once the premium is paid.
• Higher monthly premium. You pay more up front for that predictability, and the premium generally rises with age.
• Drugs are separate. You add a stand-alone Part D plan, so it’s two cards instead of one.

How to choose

The honest answer depends on a handful of personal facts, not on which plan looks cheaper on paper:

• Your doctors. Are the ones you want already in a given Advantage network — or do you want the freedom to see anyone?
• Your prescriptions. Which option covers your specific drugs at the lowest total cost?
• Travel. If you spend months elsewhere, Medigap’s nationwide freedom matters more.
• Budget and risk. Lower premium with more variable costs, or a higher premium with fewer surprises?

The one timing trap

Here’s the detail that catches people. When you first turn 65 and enroll in Part B, you get a 6-month Medigap Open Enrollment window where no carrier can turn you down or charge you more for your health. If you start on Medicare Advantage and later decide you’d rather have Medigap, that guaranteed window may be gone — and in Ohio, carriers can then make you pass medical underwriting. So the choice you make at 65 isn’t always easy to reverse later.

There’s no universally better option — only the one that fits your doctors, your drugs, and how you like to handle risk. That’s exactly what a no-pressure conversation is for.