Medicare Advantage vs. Medicare Supplement. Which one is right for you?

Once you've signed up for Medicare's Hospital and Doctor coverage (Parts A and B), you face a choice that will shape your healthcare experience for the next several years. You can layer a Medicare Supplement (Medigap) policy on top of Original Medicare and add a standalone Prescription drug plan (Part D) — or you can roll the whole thing into a Medicare Advantage (Part C) plan that bundles Hospital, Doctor, and Prescription drug coverage, plus usually some extras under a private carrier. Both are legitimate. Neither is universally better. But they work very differently, and the wrong choice for your specific life is expensive.

Here's the honest comparison, in plain English.

The two paths, side by side

	Medicare Advantage	Original Medicare + Medigap + Prescription drug plan (Part D)
Monthly premium (typical CT)	$0–$50 plus your Doctor coverage (Part B) premium	$150–$300 (Plan G) plus $40–$60 (Prescription drug, Part D) plus Doctor coverage (Part B)
Network	HMO or PPO — in-network only (HMO) or in-network preferred (PPO)	Any provider that accepts Medicare, anywhere in the U.S.
Out-of-pocket on a bad year	Up to the plan's annual MOOP — $4,000 to $9,000	$257 (the Plan G deductible) plus drug costs
Drug coverage	Usually included	Bought separately
Dental, vision, hearing	Often included	Not included — bought separately
Referrals to specialists	Often required (HMO)	Not required

What Medigap actually does

A Medigap policy is a private supplemental plan that pays the share Medicare doesn't. There are ten standardized Medigap plan types (A, B, C, D, F, G, K, L, M, N), and the benefits within each letter are identical across carriers — the carrier sets the price, the federal government sets the rules. Plan G is the most commonly recommended for new enrollees: it covers everything except the small annual Doctor coverage (Part B) deductible ($257 in 2026).

The trade for that coverage is a higher monthly premium. The trade you get back is predictability: once you've paid the deductible, your medical bills for the rest of the year are essentially zero. No copays at the specialist. No 20% coinsurance on the hospital bill. No surprise out-of-network charges.

What Medicare Advantage actually does

A Medicare Advantage plan is a private bundled policy that takes over the whole job. You're still in Medicare; you're just having the carrier administer it. The carrier negotiates a network of providers, sets copays, manages prior authorizations, and bundles in prescription drug coverage and often extras like dental, vision, hearing, and a gym membership.

The trade you get is a much lower monthly premium — often $0 in Connecticut. The trade you give is network restrictions and copays at the point of service. On a healthy year, Advantage is cheap. On a year with a major hospitalization, you're out-of-pocket up to the plan's annual maximum (Maximum Out-Of-Pocket, or MOOP) — which can run $4,000 to $9,000 depending on the plan.

The trap most people fall into

There's a quirk in the law most agents won't mention: when you first enroll in Medicare at 65, you have a guaranteed-issue right to buy any Medigap policy you want at standard rates, regardless of your health history. That window lasts six months from the date your Doctor coverage (Part B) starts.

After that window closes, in Connecticut, Medigap carriers are allowed to ask health questions and decline you for pre-existing conditions. Connecticut has somewhat friendlier Medigap rules than most states — it allows a continuous open enrollment in some circumstances — but the practical reality is that most people who pick Advantage at 65 and try to switch to Medigap at 75 because they got sick will face medical underwriting at the moment they need it most.

This is the trap. Medicare Advantage is cheap and feels like the right call when you're 65 and healthy. Five or ten years later, when you've developed a condition that would benefit from the broader access of Original Medicare + Medigap, the door has narrowed. Not closed — narrowed.

Who each one is right for

Medicare Advantage tends to be the right answer if:

• You're healthy, expect to stay healthy, and are comfortable with that bet
• You don't travel out of state much
• You'd rather pay copays as you go than premiums up front
• You value bundled extras (dental, vision, hearing, gym)
• You're price-sensitive on monthly premiums

Original Medicare + Medigap + Prescription drug plan (Part D) tends to be the right answer if:

• You travel and want any-Medicare-provider-in-the-country access
• You have specific specialists or hospital systems you don't want to lose access to
• You have a chronic condition or family history that makes a high-cost year likely
• You have a low tolerance for surprise medical bills
• You're comfortable paying higher monthly premiums for predictability

If you're dual-eligible

If you're 65+ and on Medicaid (HUSKY C in Connecticut), the Advantage-vs-Supplement question is different. You'll usually want a Dual-Eligible Special Needs Plan (D-SNP) — a specific type of Medicare Advantage plan designed for people on both programs, which, for those who qualify, can include $0 copays, broader benefits, and built-in care coordination. Standard Advantage and Medigap usually don't make sense in this scenario. More on coordinating Medicare and Medicaid here.

The honest version

I write both. I don't get a meaningfully larger commission for either, and I don't get penalized by the carrier for steering away from a plan that doesn't fit. The right answer is the one that matches your network, your prescriptions, your travel, and your tolerance for variability. The wrong answer is whatever you pick in a hurry because of a TV commercial.

Sources and further reading

• Medicare.gov — Medigap and Medicare Advantage plan finder
• State of Connecticut Insurance Department — Medigap plan filings
• CHOICES program (CT) — free unbiased Medicare counseling

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