Medigap vs Medicare Advantage — How the Costs Are Structured
Medigap and Medicare Advantage do not cost more or less than each other — they put the cost in different places. One front-loads predictable premiums, the other front-loads less and exposes you to out-of-pocket charges up to a yearly maximum. Here is the structure of each, in figures CMS publishes, with no plan named.
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Original Medicare with a supplement
Cost mostly known in advance
You pay the Part B premium plus a monthly supplement premium, and the supplement then covers most of what Original Medicare leaves behind. More of your money goes out in predictable monthly amounts, and less of it arrives in the year you are ill.A Medicare Advantage plan
Cost mostly follows use
You still pay the Part B premium, plus whatever the plan charges, which is often nothing. In exchange you pay as you use care — copays and coinsurance — until you reach the plan's yearly in-network maximum, at which point the plan covers the rest.
Neither one is the cheap option
They are two arrangements of the same underlying costs, not a better and a worse deal. One is cheaper in a quiet year and dearer over a decade of premiums; the other is the reverse in a year with a hospital stay in it. Which suits a particular person depends on their health, their doctors, and how much they travel — and no calculator, this one included, knows any of those.Why Medigap policies are named after letters
They are standardized. A policy with a given letter covers the same basic benefits whoever sells it, so between two companies selling the same letter the difference is price and service, not coverage.
Letters open to new enrollees
A, B, D, G, K, L, M, N
- Standardized letters in all
- 10
Sold by many companies, identical in basic benefits, different in price.Letters closed to newer enrollees
C and F
Policies sold to people who became eligible for Medicare on or after January 1, 2020 are not allowed to cover the Part B deductible, which closed these letters to them. Anyone eligible before that date who had not yet enrolled may still be able to buy one.
The yearly ceiling, and where it does not exist
Original Medicare alone
No yearly limit at all
There is no cap on what you can pay out of pocket in a year. That is the structural gap the two arrangements above each close in a different way, and it is the single most important fact on this page.Medicare Advantage, 2026
At most $9,250 in network
A ceiling on what plans may charge, set by CMS, not what any particular plan does charge. Plans may and do set lower limits.
The details worth knowing before you look at anything
- Medigap policies are standardized by letter. A policy with a given letter covers the same basic benefits no matter which company sells it or where you live, so the difference between two companies selling the same letter is price and service, not coverage.
- Plans C and F are closed to anyone who turned 65 on or after January 1, 2020, because Medigap policies sold to people new to Medicare from that date are not allowed to cover the Part B deductible. If you were eligible for Medicare before January 1, 2020 but had not yet enrolled, you may still be able to buy them. Plans D and G give the same benefits apart from that deductible.
- Massachusetts, Minnesota and Wisconsin standardize Medigap policies differently, so the letter system on this page does not describe what is sold there.
- Plans K and L are the two standardized plans with their own annual out-of-pocket limit: $8,000 for Plan K and $4,000 for Plan L in 2026. The other eight lettered plans have no out-of-pocket limit of their own.
- Original Medicare by itself has no yearly cap on what you pay out of pocket. That is the structural gap Medigap and Medicare Advantage each close in a different way.
- For 2026 CMS caps the in-network out-of-pocket limit a Medicare Advantage plan may set at $9,250 (the mandatory MOOP limit, down $100 from $9,350 in 2025). A plan may choose a lower limit — CMS also defines an intermediate limit of $6,750 and a lower limit of $4,200 — and the combined in-network and out-of-network limit for a mandatory-MOOP plan may not exceed $13,900. These are ceilings on what plans may charge, not what any particular plan does charge.
- This pack records structural facts only. It names no insurance company and ranks no plan, by design: comparing or steering toward specific Medicare Advantage or Part D plans is regulated marketing activity, and this site stays on the education side of that line. Use Medicare's own Plan Compare, or a licensed broker, to look at actual plans.
The window that does not come back
For six months from the first month you are 65 and enrolled in Part B, an insurer cannot refuse you a supplement or charge you more because of your health history. It happens once. Work out when yours runs, or put your own figures into the total cost estimator to see the two shapes side by side.Where to take a plan question
We take no money from any insurer and name none, so we are not the place to settle what you buy. These three are, and all of them are free.
Verified 2026-08-02 against Medicare.gov, "Compare Medigap plan benefits" (standardized plan letters, plans closed after January 1 2020, Plan K and L out-of-pocket limits); the Advantage out-of-pocket maximum is from CMS, "CY 2026 MOOP and Cost Sharing Limit Calculations" (https://www.cms.gov/files/zip/cy-2026-moop-and-cost-sharing-limit-calculations.zip), file CSV/MOOP Limits.csv, Table 1 row E (effective 2026-01-01)
Estimate only — not financial, tax, legal, or insurance advice. Only MEDICARE can determine your actual amounts.
Official source: Medicare.gov — Medigap benefits by standardized plan letter ↗
🎓 Understand this tool
What it is
A structural comparison of how the two supplemental arrangements distribute cost across a year — standardized Medigap plan letters, which letters are closed to newer enrollees, and the ceiling CMS sets on what a Medicare Advantage plan may charge in network before it must stop.
How it works
Medigap policies are standardized by letter, so the same letter buys the same basic benefits from any company in most states, and price and service are what differ. Medicare Advantage plans instead set their own out-of-pocket maximum within limits CMS publishes annually. Every figure on this page is a structural fact from a CMS or Medicare.gov source, recorded with the date it was checked; no insurer is named and no plan is ranked.
Getting the most from it
- Read the two cost shapes first. One puts more into a predictable monthly premium, the other puts less there and more into the year you are ill.
- Note which plan letters are closed to people who became eligible on or after January 1, 2020, and which two letters carry an out-of-pocket limit of their own.
- Check whether you live in Massachusetts, Minnesota or Wisconsin — those three states standardize supplemental policies differently, and the letter system does not describe them.
- When you are ready to look at what is actually sold near you, use the Plan Finder on medicare.gov, call 1-800-MEDICARE, or book your state SHIP counselor, who takes no commission.
Reading your result
Read the figures as ceilings and structures rather than prices. The Advantage limit is the most CMS allows a plan to charge in network, not what any particular plan charges, and the plan letters describe what a policy must cover, not what it costs where you live.
What it can't tell you
This page holds no prices, names no insurer and ranks nothing, by design: marketing or steering toward particular Medicare plans is regulated activity, and this site stays on the education side of that line and takes no money from any insurer. What is available to you, at what price, with which doctors in network, is a question for Medicare's own tools and your SHIP.
Frequently asked questions
It is a difference in shape, not in size. Original Medicare with a Medigap policy puts most of the cost into a monthly premium you know in advance and less into the year you are ill. An Advantage plan reverses that: a lower premium, and charges as you use care, up to the plan's yearly in-network maximum.
Related calculators
Total Cost Estimator
Nobody publishes one number for what a year of Medicare costs a household, because the pieces live in separate documents. This estimator adds them: the Part B premium, any IRMAA surcharge, deductibles, and the drug or supplement premium you supply. Original Medicare and Advantage are shown as two shapes of cost, without a verdict.
Enrollment Dates
Your seven-month Medicare sign-up window is worked out from your birthday, and being born on the first of a month shifts the whole thing a month earlier. Enter your date of birth to estimate your own dates, see when coverage would start, and download them to your calendar. No email address required.
Part B Premium
The standard Medicare Part B premium and annual deductible for 2026, taken straight from the CMS notice that set them, with every year back to 2016 so you can see how fast this line item has actually risen. Higher earners pay more through IRMAA; this page shows the base figure everyone starts from.
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