Medicare Supplements are standardized by law, which is the single most useful thing to know about them. A Plan G is a Plan G at every company. The benefits are identical, set by federal rules — so the only things that actually differ between carriers are the price, the rate history, and how pleasant they are to deal with.
That means shopping Medigap is genuinely simple, once you know which letter you want.
The three that matter
| Plan | What it covers | Who it suits |
|---|---|---|
| Plan G | Everything Original Medicare doesn't, except the Part B deductible. Once that's paid, your covered costs are essentially zero for the year. | The most popular choice for people newly eligible. Highest premium of the three, and the most predictable — you'll rarely see another bill. |
| Plan N | Similar to G, but you pay small copays — up to $20 for some office visits, up to $50 for an emergency room visit that doesn't lead to admission — and it doesn't cover Part B excess charges. | People comfortable with modest copays in exchange for a lower monthly premium. Often the better value if you don't see doctors often. |
| High-deductible G | Identical coverage to Plan G, but you pay a deductible (a few thousand dollars) before it kicks in. In return, the premium is dramatically lower. | Healthy people who want catastrophic protection rather than first-dollar coverage, and who could absorb the deductible in a bad year. |
Plan F still exists, but it's closed to anyone who became eligible for Medicare on or after January 1, 2020. If you already have it you can keep it; if you're newly eligible you can't buy it, which is why Plan G became the default.
Medicare roughly halves the odds of owing money on medical bills.
Adults who say they currently owe money because of medical or dental bills.
Your share of covered costs in a year, 2026.
Roughly the most you pay for Medicare-covered care before the plan picks up the rest.
Why the letter matters less than the timing
Here's the part that costs people the most money, and it isn't about which plan you pick.
Your Medigap Open Enrollment window is six months long, starting when you're 65 or older and enrolled in Part B. During it, you can buy any Supplement sold in your state with no health questions at all. A carrier cannot decline you or charge you more for your health history, and if you had health coverage before Medicare, it generally cannot make you wait either.
Once it closes, in most states a carrier can underwrite you — ask about your health, and say no. People who start on an Advantage plan and try to move to a Supplement three years later often discover this the hard way. One safety net worth knowing: if you join an Advantage plan when you first become eligible at 65, federal rules give you twelve months to change your mind, return to Original Medicare and buy a Supplement without health questions.
So the honest advice: if there's any chance you'll want a Supplement, the cheapest and safest time to get one is that window.
Your enrollment windows, on one line.
Months before and after the month you turn 65.
Since the benefits are identical, what should you compare?
- Price today — the same Plan G can vary by hundreds of dollars a year between carriers for identical coverage. This is the clearest case in all of insurance for shopping around.
- Rate increase history — a low introductory price means little if the carrier raises rates aggressively. A company's track record over five or ten years tells you more than this year's quote.
- How they price by age — some carriers charge based on your age at issue, some on your current age, some the same for everyone in an area. It changes what you'll pay at 80, not just at 65.
- Household discounts — many carriers reduce the premium if a spouse or partner also enrolls. Often 5–14%, and frequently unmentioned.
That's what I do when you ask me to shop it: same benefits, sorted by price and rate stability, with the household discount applied where it exists.
A Supplement doesn't include drug coverage
Worth stating plainly, because it surprises people. Original Medicare plus a Supplement covers your medical care but not your prescriptions — you add a separate Part D plan for that. It's a small extra premium, and choosing the right one depends entirely on which medications you take.
Bring me your medication list and I'll check it against the formularies rather than guessing.