Key takeaways
- Original Medicare has no yearly cap on what you pay; Medicare Advantage caps in-network costs at $9,850, but limits your doctors and may need prior authorization.
- Original Medicare plus a Medigap Plan G leaves you paying mainly the Part B deductible each year — but Medigap is cheapest and easiest to buy when you first join at 65.
- You can switch between the two every fall (October 15 to December 7), but going back to Medigap later usually means medical underwriting in most states.
Medicare gives you two ways to get your coverage, and the choice is hard to undo. Original Medicare plus a supplement (Medigap) costs more every month but leaves you free to see almost any doctor. Medicare Advantage usually costs less per month and caps your yearly spending, but you give up that freedom. The right answer depends on your health, your doctors, your budget and how much risk you can carry.
Open enrollment for 2027 runs October 15 to December 7, 2026, and changes take effect January 1, 2027. There is a second window, Medicare Advantage open enrollment, from January 1 to March 31, 2027, for people already in a Medicare Advantage plan.
The two options, side by side
| Original Medicare + Medigap | Medicare Advantage (Part C) | |
|---|---|---|
| What it is | Part A (hospital) + Part B (medical) from the government, plus a private Medigap policy and a separate Part D drug plan | One private plan that replaces A and B, usually includes drug coverage (Part D) and extras |
| Monthly premium | Part B premium + Medigap premium + Part D premium | Part B premium (you still pay it) + the plan’s premium — CMS projects the average at about $12 a month in 2027, and many plans are $0 |
| Yearly cap on your costs | None on its own — Medigap Plan G leaves you paying mainly the Part B deductible each year | Yes — CMS lets plans set the in-network cap as high as $9,850 in 2027 ($14,800 for a PPO counting out-of-network care). The median plan’s cap is about $6,600 |
| Doctors | Any doctor or hospital in the U.S. that accepts Medicare — no network, no referrals | A network, usually an HMO or PPO. Out-of-network care costs more or is not covered at all |
| Prior authorization | No | Yes — the plan can require approval before some services, and can deny care Medicare would cover |
| Prescription drugs | Separate Part D plan; 2027 out-of-pocket drug costs are capped at $2,400 | Usually included; the same $2,400 drug cap applies |
| Extras | None — dental, vision and hearing are not covered | Often includes some dental, vision, hearing, gym and over-the-counter benefits, but the value varies widely |
| Travel | Covered anywhere in the U.S. | Emergency care is covered anywhere, but routine care outside your network area usually is not |
What the numbers are for 2027
- Part B premium and deductible for 2027 have not been announced yet. CMS usually announces them in November; for 2026 the standard premium is $202.90 a month and the deductible is $283. The Medicare Trustees project $209.50 and $292 for 2027 — that is a projection, not the official amount, so do not plan on it exactly.
- Medicare Advantage out-of-pocket cap: up to $9,850 in-network in 2027 (up from $9,250 in 2026), and up to $14,800 for a PPO counting out-of-network care. Plans choose their own cap at or below the ceiling; the median plan sets about $6,600.
- Part D drug cap: $2,400 out-of-pocket in 2027, under either option.
- Part B premium in a Medicare Advantage plan: you still pay it. A “$0 premium” Advantage plan means $0 on top of Part B, not $0 in total.
When Original Medicare plus Medigap wins
- You have a serious or unpredictable condition. With Plan G, your out-of-pocket costs are mainly the Part B deductible each year, however much care you need. In a Medicare Advantage plan, a bad year can cost you up to the plan’s cap — $9,850 at the top end.
- Your doctors matter. Specialists, cancer centres and hospitals of your choice are available under Original Medicare as long as they accept Medicare. Under Advantage, they must be in the plan’s network.
- You travel or split time between states. Original Medicare works the same everywhere in the U.S. Advantage networks are local; snowbirds often find their plan does not cover routine care in their second home.
- You want no surprises. No prior authorization, no network changes in January, no plan leaving your county. Medigap premiums rise with age, but the coverage does not change.
The catch is the premium: Part B plus Medigap plus Part D can run several hundred dollars a month, every month, whether you use care or not.
When Medicare Advantage wins
- You are healthy and want the lowest monthly cost. Many plans charge $0 on top of Part B, and the out-of-pocket cap protects you from a catastrophic year.
- You like your local network. If your doctors and hospital are in the plan and you rarely travel, the network costs you nothing.
- You want the extras. Dental, vision, hearing and gym benefits are real, though they are usually modest — read the plan’s summary of benefits, not the advertisement.
- You want one card and one plan. Advantage bundles hospital, medical and usually drug coverage, with one out-of-pocket cap for medical care.
The catch is the other side of the same deal: copays on every visit and service, prior authorization, and a network that can change each year. In a heavy-care year the copays add up to the plan’s cap, which can be more than a year of Medigap premiums would have cost.
The decision that is hard to reverse: Medigap
This is the part most people miss. When you first join Part B at 65, you get a six-month Medigap open enrollment period in which insurers must sell you any Medigap policy at the best available rate, regardless of your health. After that window closes, in most states insurers can refuse you or charge more based on medical underwriting.
That means:
- If you start with Original Medicare plus Medigap at 65, you can switch to Medicare Advantage later with no penalty.
- If you start with Medicare Advantage and want to move to Medigap years later, you will usually have to pass underwriting — and if your health has worsened, you may be refused or priced out.
A few states (including Connecticut, Maine, Massachusetts and New York) protect Medigap access year-round. Everywhere else, treat the first choice as the one that keeps your options open. If you think you may want Medigap one day, buying it at 65 is the cheapest time to do it.
How to choose, in order
- List your doctors and drugs. Check whether they are in the Advantage plans available in your county, and what each plan charges for your drugs. Use the Medicare Plan Finder at medicare.gov — do not decide from a mailer.
- Add up a bad year, not a good one. For each option, add 12 months of premiums plus the out-of-pocket cap (Advantage) or the Part B deductible plus premiums (Original + Plan G). The option that is cheapest in a healthy year is often the most expensive in a bad one.
- Check the Annual Notice of Change. If you already have a plan, it arrives by September 30. Premiums, drug lists, networks and out-of-pocket caps change every year — a plan that was right for 2026 may not be right for 2027.
- Think about five years from now, not one. Health changes. The plan that fits a healthy 65-year-old may not fit the same person at 72, and by then Medigap may be closed to them.
- Get free, unbiased help. Your State Health Insurance Assistance Program (SHIP) gives free Medicare counselling — find yours at shiphelp.org. It does not sell plans.
Switching, and the deadlines
- October 15 to December 7, 2026: open enrollment. Join, switch or drop a Medicare Advantage or Part D plan; switch from Original Medicare to Advantage or back. Changes start January 1, 2027.
- January 1 to March 31, 2027: Medicare Advantage open enrollment. If you are in a Medicare Advantage plan, you can switch to another Advantage plan or back to Original Medicare (with a Part D plan). You cannot use this window to join Advantage from Original Medicare.
- Any time: if you move, lose coverage, or qualify for Extra Help or Medicaid, a special enrollment period may apply. Moving from Advantage back to Original Medicare outside these windows is generally not possible.
If you switch from Advantage back to Original Medicare, remember to add a Part D drug plan and, if you can get one, a Medigap policy — Original Medicare on its own has no drug coverage and no out-of-pocket cap.
Sources
- Medicare.gov: Joining a plan (enrollment periods)
- Medicare.gov: Medicare Plan Finder
- CMS: 2026 Medicare Parts A and B premiums and deductibles
- SHIP: State Health Insurance Assistance Programs