Medicare Advantage vs. Medicare Supplement: What's the Difference?

If you're approaching 65 — or helping a parent who is — you've probably noticed that Original Medicare doesn't cover everything. There are deductibles, coinsurance, and no annual cap on what you might owe. Two products exist to fill those gaps, and they work in almost opposite ways. Choosing between them is one of the most important decisions you'll make about your coverage.

The confusing part is the names. Medicare Advantage and Medicare Supplement sound like cousins, but they solve the same problem from completely different directions. One replaces the way you get your Medicare. The other sits alongside it. You generally pick one path or the other — not both.

First, what Original Medicare leaves on the table

Original Medicare is Part A (hospital) and Part B (medical). It covers a lot, but it has real gaps. In 2026, you'd face a $1,736 hospital deductible per benefit period, a $283 annual Part B deductible, and a 20% coinsurance on most Part B services — with no annual limit on that 20%. It also doesn't include prescription drug coverage on its own. Both Medicare Advantage and Medigap exist to address these gaps.

What is Medicare Advantage (Part C)?

A Medicare Advantage plan is offered by a private insurance company approved by Medicare. When you enroll, the plan takes over administering your Part A and Part B benefits — and most plans roll in prescription drug coverage (Part D) plus extras Original Medicare never offered.

• Often low or $0 monthly premium (you still pay your Part B premium — $202.90 in 2026).
• Networks matter. Most plans are HMOs or PPOs, so you'll usually pay less by staying in-network, and may need referrals.
• You pay as you go — copays and coinsurance for visits, tests, and stays.
• A built-in safety net. Every plan has an annual out-of-pocket maximum; for 2026 the in-network cap can be no higher than $9,250, and many plans set theirs lower.
• Extras are common — many plans include dental, vision, hearing, fitness benefits, and more, though specifics vary by plan and area.

What is Medicare Supplement (Medigap)?

A Medigap policy works in the opposite direction. You keep Original Medicare exactly as it is, and the Medigap plan steps in to pay the deductibles, coinsurance, and copays that Medicare leaves to you. It's standardized insurance — a Plan G from one company covers the same gaps as a Plan G from another, so you're comparing price and service, not fine print.

• No networks. You can see any doctor or hospital in the country that accepts Medicare — no referrals.
• Predictable costs. A higher fixed monthly premium in exchange for little to no surprise at the point of care.
• Standardized lettered plans (A through N). Plan G is the most popular choice for people newly eligible today.
• Drugs are separate. Medigap doesn't include prescriptions — you'd add a stand-alone Part D plan (2026 drug out-of-pocket cap: $2,100).
• Most plans have no out-of-pocket maximum because they're designed to cover the gaps directly. (The exceptions, Plans K and L, cap out-of-pocket at $8,000 and $4,000 respectively in 2026.)

Side by side

So which one is right for you?

There's no universally "better" choice — it comes down to how you value monthly cost versus flexibility and predictability, and how you tend to use care.

The bottom line

Medicare Advantage trades some flexibility for a lower premium and bundled extras, with your spending capped each year. Medicare Supplement trades a higher premium for broad provider freedom and few surprises at the doctor's office. Both are legitimate, widely-used paths — the right one depends on your budget, your doctors, your prescriptions, and how much predictability matters to you.

This is exactly the kind of decision where a quick conversation with a licensed agent saves a lot of second-guessing. We can walk through your specific doctors, medications, and budget and lay out your options clearly — no pressure, no jargon.