Medicare Advantage vs Medigap: The Real Tradeoffs

The fork, in plain terms

Quick map first. Road one is Original Medicare: Part A (hospital) and Part B (doctors and outpatient care), run by the federal government. Many people add two things to it: a Medigap policy, also called a Medicare Supplement or just a gap plan, which is private insurance that fills the cost gaps Original Medicare leaves, and a standalone Part D drug plan. Road two is Medicare Advantage, also called Part C: a private plan the government pays to deliver your Part A and Part B benefits, usually with drug coverage built in. Source: Medicare.gov, your coverage options, 2026.

Both roads are real Medicare, and neither one is a trick. They just trade different things, and those trades come down to five questions.

Tradeoff 1: the monthly bill vs. the bad-year bill

On the Advantage road, the plan's own premium (its monthly bill) is often low, and some plans charge nothing beyond the standard Part B premium, which is $202.90 a month in 2026. Source: CMS, 2026 Medicare Parts A & B fact sheet, 2026. The tradeoff is that you pay as you go: copays (flat fees per visit) and coinsurance (a percentage of the bill) through the year, up to the plan's yearly in-network out-of-pocket maximum. That maximum is the most you can pay in a year for covered Part A and Part B care from providers in the plan's network. Prescription drugs sit outside it and have their own separate cap, further down this page. The maximum differs plan to plan. For 2026, federal rules say a plan can't set its in-network limit above $9,250. Source: CMS, CY 2026 MOOP and Cost Sharing Limit Calculations, 2026. Most plans set theirs lower than that ceiling, but how much lower varies a lot, so read the number on the plan you're actually looking at rather than assuming the cap. The "lower than the cap" pattern comes from independent analyses of CMS's 2026 plan data. CMS publishes the limit, not the typical amount.

On the Medigap road, you pay more every month whether or not you use care: the Part B premium plus a Medigap premium that depends on the plan letter, the company, where you live, and your age. (Medigap plans are standardized by letter, so a Plan G covers the same things no matter which company sells it. Our Plan G vs Plan N guide compares two of those standardized letters.) In exchange, the policy fills most of the gaps in Original Medicare, including the 20% share Part B leaves to you after its $283 deductible (the amount you pay before coverage kicks in). That 20% has no upper limit on its own, which is the main job people hire a Medigap policy to do. Source: CMS, 2026 Medicare Parts A & B fact sheet; Medicare.gov, 2026.

So the first question isn't which road is cheaper. It's which bill you'd rather pay: a higher, predictable one every month, or a lower one now with more exposure in a heavy-care year. If you want every 2026 number in one place while you think about it, our 2026 Medicare costs guide has the full table.

Tradeoff 2: any doctor vs. a network

Original Medicare has no network. You can see any doctor or hospital in the country that accepts Medicare, and you generally don't need a referral to see a specialist. That freedom matters most if you travel, split the year between two states, or want care at a specific hospital. Source: Medicare.gov, 2026.

A Medicare Advantage plan works more like the insurance many of us had at work. It usually has a network of doctors and hospitals, it can require referrals, and it comes with its own rules, and those rules vary from plan to plan. Source: Medicare.gov, 2026.

Neither setup is wrong. If your doctors are in the network and you stay local, the network may never cost you a thing. The question is what your actual life looks like: which doctors you want to keep, and where you'll be living in February.

Tradeoff 3: the one-way door

This is the tradeoff too few people hear about before they choose. The door between these two roads doesn't swing both ways evenly. Moving from Medigap into an Advantage plan during an enrollment window is straightforward. Coming back is not guaranteed.

Here's why. When you're 65 or older and first enrolled in Part B, you get a one-time Medigap open enrollment period. It lasts 6 months, and during it, companies have to sell you any policy they offer without medical underwriting, meaning no health questions used to accept or reject you, and no higher price because of your health history. Source: Medicare.gov, when you can buy a Medigap policy, 2026.

Once that window closes, the rules flip. In most states, a Medigap company can ask about your health, charge you more, or turn you down. Some situations restore a guaranteed right to buy, and some states add protections of their own, so check what applies where you live before you count on it. Our guide to how switching back to Medigap really works walks through the protected situations and the deadlines. Source: Medicare.gov, Medigap basics, 2026.

The honest question to ask yourself is simple: if you start on the Advantage road, are you comfortable knowing the road back to Medigap may involve health questions later?

Tradeoff 4: drug coverage, built in or added on

On the Advantage road, drug coverage usually comes built into the plan. On the Medigap road, it never does. Medigap policies don't include drug coverage, so you add a standalone Part D drug plan with its own premium. Source: Medicare.gov, 2026. For 2026, the base Part D premium is $38.99, actual premiums vary by plan, and a plan's deductible can run anywhere from $0 up to $615. Source: CMS, 2026 Part D bid information, 2026.

One thing is the same on both roads: the yearly cap on what you pay out of pocket for covered drugs, which is $2,100 in 2026. Drug coverage inside an Advantage plan is still Part D coverage, so the cap applies either way. Source: CMS, Final CY2026 Part D Redesign Program Instructions, 2026.

So the homework is identical on both roads: before you commit to anything, check your specific prescriptions against the plan's formulary, its list of covered drugs. A plan that covers your neighbor's medications cheaply may treat yours very differently.

Tradeoff 5: the extras, and the word "some"

Original Medicare doesn't cover routine dental, vision, or hearing care, and Medigap doesn't either, because Medigap only fills gaps in what Original Medicare already covers. Source: Medicare.gov, your coverage options, 2026. Advantage plans commonly include some of these benefits, and for plenty of people they're a real draw.

But sit with the word "some" for a second. These extras are usually capped by dollar allowances, they vary a lot by plan and by location, and they can change from one year to the next. A plan advertising "dental" tells you almost nothing by itself. The number that matters is the dollar allowance in the plan documents, and whether it covers the work you genuinely expect to need. If you're already on an Advantage plan, next year's changes show up in the letter your plan sends called the Annual Notice of Change. Our guide to reading your ANOC letter shows where benefit changes hide.

The five questions to bring to the decision

Here they all are in one place. They're the same questions a good counselor would walk you through.

1. Which bill: a predictable monthly premium, or pay-as-you-go with a yearly maximum?
2. Network: are my doctors in it, and do I travel?
3. The one-way door: am I okay if the road back to Medigap involves health questions later?
4. Drugs: are my prescriptions on the plan's formulary?
5. Extras: what's the real allowance, in dollars, in writing?

Notice there's no scoreboard. These two roads trade different things, and your health, your budget, your doctors, and your zip code decide which tradeoffs are cheap for you and which ones are expensive. Anyone who hands you the answer before asking you these questions is selling something.

Questions people ask

Is Medigap better than Medicare Advantage?

Neither one is better across the board, and much of the content that says otherwise was written by someone paid on the answer. The two arrangements trade different things, and the five questions above are how you find out which tradeoffs are cheap in your situation and which ones would cost you.

Can I have both Medicare Advantage and Medigap?

No. A Medigap policy only works alongside Original Medicare, not with a Medicare Advantage plan. Choosing the Advantage road means the Medigap piece doesn't come with you. Source: Medicare.gov, Medigap basics, 2026.

Why do people call Medicare Advantage "the free plan"?

Because some Advantage plans charge no plan premium at all, and ads lean on that hard. What's easy to miss is that you still pay the standard Part B premium, $202.90 a month in 2026, on either road, and you still pay the plan's copays and coinsurance as you use care. So "free" describes one line of the bill, not the year's total cost. Source: CMS, 2026 Medicare Parts A & B fact sheet, 2026.

If I pick Medicare Advantage at 65, can I switch to Medigap later?

You can always leave a Medicare Advantage plan and return to Original Medicare during set windows each year. What's not guaranteed is the Medigap policy to go with it: after your one-time 6-month window, most states let companies use medical underwriting unless a specific protection applies. The limited situations that restore a guaranteed right to buy, and the deadlines attached to them, are in the switching back to Medigap guide. Source: Medicare.gov, Medigap basics, 2026.

Whichever way you're leaning, don't decide from one page, including this one. The Plan Finder at Medicare.gov shows the actual Advantage and drug plans for your zip code with real prices, and every state offers free one-on-one counseling through SHIP, the State Health Insurance Assistance Program, where the counselor knows your state's Medigap rules and doesn't sell anything. The official contacts are below. Bring the five questions with you.