If you’ve ever tried to read what a Medicare Supplement plan covers and walked away more confused than when you started, you’re not alone. The letters, the percentages, the fine print — it feels designed to make your eyes glaze over.
Here’s the thing most explanations skip: a Medicare Supplement (Medigap) plan doesn’t pay for your health care. Original Medicare pays first. The Supplement fills in the gaps Medicare leaves behind — the deductibles, coinsurance, and copays that are entirely your responsibility. That’s where the real money surprises live.
Not affiliated with Medicare or any government agency.
The gaps Original Medicare leaves you
Original Medicare has two main parts, and both leave bills on your kitchen table.
Part A: the hospital deductible
When you’re admitted to the hospital, Part A covers most of it — after you pay the inpatient deductible for each benefit period. That’s a four-figure number, and it resets more than once a year if your hospitalizations are spaced out.
Part B: the 20% that has no ceiling
This is the big one. Part B covers doctor visits, outpatient procedures, lab work, imaging, and preventive care. After the annual Part B deductible, you typically pay 20% of every Medicare-approved bill — with no out-of-pocket maximum.
Read that again. No ceiling. A $60,000 outpatient surgery means roughly $12,000 of coinsurance. A series of cancer treatments can run far higher. There’s no point at which Original Medicare says “okay, you’ve paid enough.”
And those numbers keep creeping up: the 2026 Medicare Trustees Report projects the Part B premium at $209.50/month for 2027 (up $6.60), and the Part B deductible keeps rising year after year.
What a Medigap plan fills in
Medigap plans are standardized by letter — A through N. Every plan of the same letter covers exactly the same benefits, no matter which company sells it. A Plan G from one carrier pays the same claims as a Plan G from another. (The difference is the price — and the company’s rate history.)
Here’s what the most common plans cover, in plain English:
Part A hospital deductible. Nearly every Medigap plan (all except A) covers this. That four-figure hospital bill when you’re admitted? The plan pays it.
Part B 20% coinsurance. Plans B through N cover this. This is the protection that turns “uncapped 20%” into a number you can plan around.
Part B annual deductible ($283 in 2026). Plans C and F cover it — but those letters are closed to anyone who became Medicare-eligible after January 1, 2020. For most people shopping today, Plan G is the most comprehensive option: it covers everything Plan F does except that Part B deductible, which you pay once a year out of pocket.
Part B excess charges. If a doctor doesn’t accept Medicare’s approved amount, they can legally bill up to 15% extra. Plans F and G cover these charges. Plan N does not — one of the trade-offs for its lower premium.
Foreign travel emergencies. Plans C, D, F, G, M, and N include some foreign-travel emergency coverage (with a $250 deductible and lifetime limits). Original Medicare generally doesn’t cover you outside the U.S. — this is a genuinely useful add-on for travelers.
Plan N’s copays. Plan N typically has lower premiums than Plan G, but you pay up to $20 for some office visits and up to $50 for emergency room visits that don’t lead to admission. For healthy, budget-conscious shoppers, it can be the right math.
What Medigap does NOT cover
This matters as much as what it covers. No Medigap plan covers:
- Prescription drugs. You need a standalone Part D plan for that.
- Routine dental, vision, or hearing care. No cleanings, no glasses, no hearing aids.
- Long-term custodial care. Nursing-home stays beyond Medicare’s limited skilled-nursing benefit aren’t covered.
- Cosmetic procedures or anything Medicare doesn’t approve. If Original Medicare won’t pay its share, your Supplement won’t pay either.
Anyone who tells you a Medigap plan “covers everything” is either confused or selling something. It covers Medicare-approved cost-sharing — and it does that job well. But it is not a magic shield.
The one number a Supplement protects you from
If you remember one thing from this guide, make it this: Original Medicare has no out-of-pocket maximum. A Medigap plan effectively gives you one.
The Part B deductible ($283 in 2026, rising for 2027) becomes the largest predictable medical bill in a typical year with a Plan G. Everything after that — doctor visits, specialists, outpatient surgery, lab work — is handled between Medicare and your plan. That’s the value proposition in one sentence: turning unlimited exposure into a known, budgeted number.
If rising 2027 costs have you rethinking your coverage, a Supplement review takes about 10 minutes.
How to shop one the right way
Because benefits are standardized by letter, shopping a Medigap plan is simpler than it looks:
- Pick the letter first. Decide how much risk you want to keep: G for the most coverage available to new enrollees, N for lower premiums with some copays.
- Shop the price, not the letter. Every Plan G pays the same claims. Compare premiums and the company’s track record of rate increases.
- Mind your enrollment window. When you first enroll in Part B, you get a 6-month Medigap open enrollment — no health questions, and the best rate you’ll likely ever see. Outside that window (and outside guaranteed-issue situations), carriers can require medical underwriting.
- Talk to a human before you decide. Ten minutes with a licensed producer can surface options — and gotchas — a quote website never will.
The bottom line
A Medicare Supplement doesn’t make health care cheap. It makes it predictable. In a year when Part B premiums and drug deductibles are climbing again, predictability is worth more than it’s ever been.
Questions? Call 1-877-752-1350 to speak with a licensed insurance producer.
Not affiliated with Medicare or any government agency. Insurance solicitation from DT Senior Insurance. A licensed insurance producer will contact you.