Medicare·10 min read

Medicare Supplement vs. Medicare Advantage: The Full Comparison

Medigap and Medicare Advantage are very different products. Here's the straight-talk comparison so you can pick the right one for your situation.

Key Takeaways

1
Medicare Supplement (Medigap) lets you see any doctor that accepts Medicare; Advantage uses a network.
2
Supplement has higher monthly premiums but very low out-of-pocket costs at care time.
3
Advantage often has $0 premiums but copays at every visit and an annual out-of-pocket max.
4
Switching from Advantage back to Supplement later may require medical underwriting — choose carefully.

The fundamental difference

Medicare Supplement (Medigap) plans pay the gaps in Original Medicare — your Part A and Part B deductibles, copays, and coinsurance. You can see any doctor in the country who accepts Medicare. No referrals needed.

Medicare Advantage (Part C) replaces Original Medicare with a private plan that bundles Parts A, B, and usually D. You typically use a network of doctors, may need referrals, and pay copays at each visit.

Cost: now vs. later

Medigap Plan G (the most popular) runs $130–$200/month for most 65-year-olds. After paying your Part B deductible ($240 in 2025), you owe almost nothing for medical care.

Medicare Advantage often costs $0/month in premium, but you'll pay copays for every doctor visit, lab, and procedure — capped by the plan's annual out-of-pocket maximum (typically $5,000–$8,500).

If you stay healthy, Advantage is cheaper. If you have a major health event, Supplement is dramatically cheaper.

The network question

Medigap: any Medicare-accepting provider in the U.S. Travel doesn't matter.

Advantage: typically HMO or PPO. HMOs require you to stay in-network. PPOs allow out-of-network at higher cost. If you travel, snowbird, or have specialists out of state, this matters.

The switching trap

When you first turn 65, you have a 6-month Medigap Open Enrollment Period during which carriers cannot deny you coverage based on health. After that window closes, switching from Advantage to Supplement may require medical underwriting — and if you have any chronic conditions, you may be denied or charged sharply higher rates.

This is why we strongly recommend talking to an independent broker before your initial Medicare enrollment, not after.

Frequently Asked

Which one do most agents recommend?+

It depends on health status, budget, and travel. We've seen healthy 65-year-olds save thousands with Advantage, and we've seen dialysis patients save tens of thousands with Supplement. There's no single right answer.

Can I have both?+

No. You can only have one or the other. You can switch during the Annual Election Period each fall, but switching out of Advantage may trigger medical underwriting.

Source: Medicare.gov — Comparing Plans ↗

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