The 2027 Numbers That Drive Everything
These are the only figures used in the scenarios below, and they come from our companion guide. Some are final, some are not.
Final: the Part D maximum deductible is $700 and the Part D out-of-pocket cap is $2,400. Those are set.
Projections: the Part B premium is expected roughly between $209.50 and $221, pending CMS confirmation. The Medicare Advantage in-network out-of-pocket maximum is expected up to about $9,850. Treat both as estimates with slack around them.
IRMAA context: the final 2026 first IRMAA threshold is $109,000 single and $218,000 married filing jointly. If your income crosses the line, your Part B and Part D premiums rise on both paths, so it changes the total but not the comparison.
You pay your Part B premium no matter which path you take. The difference is everything stacked on top of it.
Quiet, Typical, and Rough: The Three Years to Compare
Quiet year. Checkups, a handful of routine visits, cheap generics. Nothing surprises you.
Typical year. A specialist workup, some imaging, a few branded prescriptions. Normal adult life with a couple of bumps.
Rough year. Surgery, a hospital stay, rehab, ongoing specialist care. The year nobody budgets for and everybody should.
The point of the three scenarios: Advantage and Medigap look very different in column one and converge hard in column three, but from opposite directions. Advantage wins the quiet year on price and punishes the rough year. Medigap charges you for calm and delivers it.
Worked Scenario: Medicare Advantage
Assumptions, all estimates: a $0-premium Advantage plan that bundles drug coverage, and a Part B premium at roughly the midpoint of the $209.50 to $221 projection, about $215 a month or $2,580 a year. Copay figures are illustrative, not quotes.
| Cost component | Quiet year (estimate) | Typical year (estimate) | Rough year (estimate) |
|---|---|---|---|
| Part B premium (projection) | $2,580 | $2,580 | $2,580 |
| Advantage plan premium | $0 | $0 | $0 |
| Copays and coinsurance | ~$200 | ~$1,500 | ~$9,850 (capped) |
| Prescription cost-sharing | ~$0 | ~$500 | ~$2,400 (capped) |
| Total (estimate) | ~$2,780 | ~$4,580 | ~$12,430 |
Two things to notice. First, copays stop at the out-of-pocket max: a $60,000 surgery bill does not scale your cost past the cap, which is the plan's real worst case. Second, the rough year total is roughly four times the quiet year total. That swing is the product you are evaluating.
Worked Scenario: Medigap Plan G Plus Part D
Assumptions, all estimates: Plan G at $175 a month ($2,100 a year) as a mid-range illustration inside the rough national range of $100 to $350 a month, which varies widely by state and age and is not a quote. Same projected Part B premium, $2,580 a year. Standalone Part D plan premium varies by plan and state, and the 2027 Part B deductible figure is pending CMS confirmation, so both are carried as line items, not fixed figures.
| Cost component | Quiet year (estimate) | Typical year (estimate) | Rough year (estimate) |
|---|---|---|---|
| Part B premium (projection) | $2,580 | $2,580 | $2,580 |
| Plan G premium (illustration) | $2,100 | $2,100 | $2,100 |
| Part D plan premium | varies by plan | varies by plan | varies by plan |
| Part B deductible (pending CMS) | deductible | deductible | deductible |
| Medical cost-sharing | ~$0 | ~$0 | ~$0 |
| Prescription cost-sharing | ~$200 | ~$900 | up to $2,400 cap |
| Total before Part D premium (estimate) | ~$4,880 | ~$5,580 | ~$7,080 |
This is the predictability point. The medical column barely moves: a quiet year and a rough year differ by about $2,200, nearly all of it drug costs under the $2,400 cap, not medical bills. Plan G absorbs the hospital stay. The premium looks high because it is doing the work the Advantage copays do later.
The Part D Piece People Forget
Medicare Advantage usually bundles drug coverage into the same plan, which is part of why the premium can read $0. Medigap does not cover prescriptions at all, so the Plan G path needs a standalone Part D plan on top of everything else.
The 2027 Part D rules are final: a maximum $700 deductible and a $2,400 out-of-pocket cap. Those two numbers bound your drug exposure either way. The part people miss is the standalone Part D premium: it is an extra monthly charge on the Medigap path that the Advantage path often rolls into one card. When you compare totals, add the Part D plan premium to the Medigap column. The scenario table above left it as a line item precisely so you fill in your real quote.
How to Read Your Plan's Summary of Benefits
Every estimate in this guide gets replaced the moment you open your plan's Summary of Benefits. Here is where the real numbers live:
Monthly premium. The plan premium row. Remember the $0 figure is only the plan's cut, not your Part B premium.
Maximum out-of-pocket. The in-network number is your real worst case for covered services on Advantage. Confirm it matches the plan year you are buying, 2027, because it can move.
Copay schedule. Primary care, specialist, ER, inpatient, imaging, each with its own copay. These drive your typical year total.
Formulary. Your exact drugs at your tiers. A cheap premium with your prescription on a high tier is not cheap. Medicare's Plan Finder at medicare.gov/plan-compare prices your drug list under each plan automatically.
Provider directory. Verify each of your doctors is in-network for next year's plan, not this year's. Networks change every fall.
The Underwriting Trap in One Paragraph
When you first enroll in Part B at 65, you get a one-time Medigap open enrollment window, typically six months, when insurers must sell you a policy at standard rates regardless of health. After that, in most states, insurers can medically underwrite you if you try to enter or re-enter Medigap, meaning higher premiums or denial at the exact moment you need coverage most. Starting on Advantage is easy to reverse in December; starting outside the window on Medigap can be close to one-way. For the full decision framework, read How to Choose Between Medicare Advantage and Medigap.
Five Questions to Ask Before December 7
1. What is my actual in-network out-of-pocket max for the 2027 plan year? Not the brochure figure, the number in the 2027 Summary of Benefits.
2. Are all my doctors and my hospital in next year's network? Check the 2027 provider directory, not this year's.
3. Where do my prescriptions land on each plan's formulary? Run your exact drug list through medicare.gov/plan-compare.
4. Can I cover the rough-year total without touching savings? On Advantage that means the Part B premium plus roughly $9,850. On Medigap it means the premiums plus the deductible.
5. Am I inside my Medigap open enrollment window, and if I let it pass, can I afford to lose it? This is the only question with no do-over.
Frequently Asked Questions
Is a $0-premium Medicare Advantage plan really free?
No. You still pay your Part B premium, and visits, scans, and hospital stays carry copays until you hit the plan's in-network out-of-pocket max, expected up to about $9,850. The scenarios above show the same $0-premium plan costing roughly $2,800 in a quiet year and roughly $12,400 in a rough year.
Why does Medigap cost so much more every month?
Because the premium buys a ceiling you never hit. Plan G covers almost all cost-sharing Original Medicare leaves behind, so a hospital year costs about the same as a healthy year. Advantage shifts that cost-sharing back to you visit by visit, which is why its premium can be $0 while its bad-year cost runs far higher.
What happens financially if I get seriously ill on each path?
On Advantage, copays and coinsurance accumulate up to the in-network out-of-pocket cap, expected up to about $9,850, on top of your Part B premium. On Original Medicare with Plan G, a serious illness year costs roughly your usual premiums plus the Part B deductible and your Part D exposure, with almost no added medical cost-sharing.
Can I switch from Medicare Advantage to Medigap later if the bills get bad?
You can switch in the Annual Election Period, but Medigap is not guaranteed after your one-time open enrollment window. In most states insurers can medically underwrite you, which can mean higher premiums or denial exactly when you are sick. Leaving Medigap for Advantage is easy; coming back can be medically gated.
Where do I verify my doctors and drugs before choosing?
Use Medicare's Plan Finder at medicare.gov/plan-compare for network membership and exact prescription pricing under each plan's formulary, for the 2027 plan year. A licensed agent or your State Health Insurance Assistance Program can also help.
What are the key 2027 Medicare numbers used in these scenarios?
Final for 2027: the Part D maximum deductible is $700 and the Part D out-of-pocket cap is $2,400. Projections pending CMS confirmation: the Part B premium roughly between $209.50 and $221, and the Advantage in-network out-of-pocket max expected up to about $9,850. The final 2026 first IRMAA threshold is $109,000 single and $218,000 married filing jointly.
Explain It to Yourself
Still fuzzy on which column matters for you? Our AI Medicare Advantage vs Medigap explainer walks through the tradeoffs in plain language. For the full decision framework, read How to Choose Between Medicare Advantage and Medigap. And plug your real quotes into the Medicare cost calculator to replace every estimate on this page with your numbers.
Plan the Cash Side
Whichever path you pick, premiums land in a monthly budget. Lay it out with our budget planner, sanity-check take-home figures with the salary converter, and run percentage math on copays and caps with the percentage calculator.
Disclaimer: This guide gives educational estimates only. It is not medical, insurance, or financial advice. Premiums, networks, formularies, and caps change yearly and vary by state and ZIP code. Plan G premiums shown are an illustration, not a quote. Confirm current figures at medicare.gov/plan-compare and with a licensed agent or your State Health Insurance Assistance Program before enrolling.