Medicare Supplement

Medigap Plan Letters, Explained Without the Jargon

MOUNT VERNON, N.Y. — If you've ever tried to shop for a Medicare Supplement policy, you've probably run into a wall of letters: Plan A, Plan G, Plan N, and more. It looks confusing, but there's actually a helpful reason those letters exist — and once you understand the system, choosing becomes a lot easier.

Here's a plain-English guide to what Medigap does, how the standardized letters work, and the small mistakes that trip people up.

What Medigap actually does

Medigap — the nickname for Medicare Supplement Insurance — is a private policy that works alongside Original Medicare (Part A and Part B). It doesn't replace Medicare. Instead, it helps pay some of the costs Original Medicare leaves behind, like coinsurance, copayments, and certain deductibles.

A few important things to know up front:

• Medigap only works with Original Medicare. You can't use it with a Medicare Advantage plan.
• It does not include prescription drug coverage. For that, you'd add a separate Part D plan.
• It doesn't cover things like dental, vision, hearing aids, or long-term care.

Mount Vernon residents live in Westchester County, where — like the rest of New York State — Medigap policies are sold by private insurance companies but regulated under both federal and state rules.

Why the letters exist

Back in the early 1990s, Medigap was a mess. Every company sold different policies, and it was almost impossible to compare them. So the federal government stepped in and standardized the plans.

Today, in most states, Medigap policies come in lettered versions: A, B, C, D, F, G, K, L, M, and N. (Plans C and F are only available to people who became eligible for Medicare before January 1, 2020.)

Here's the key point that saves people a lot of stress: every Plan G is the same Plan G, no matter which company sells it. The core benefits are set by federal rules. What changes from company to company is the price, the customer service, and sometimes small extras.

That means once you decide which letter fits your needs, your job is mostly to compare prices and the company's reputation.

What each letter generally covers

Instead of listing every benefit, think of the letters as a menu that ranges from basic to comprehensive:

• Plan A is the most basic option available in every state.
• Plans K and L have lower premiums but ask you to share more costs, up to a yearly limit.
• Plan N covers most gaps but includes small copays for some office and ER visits.
• Plan G is one of the most popular for people newly eligible, since it covers nearly everything except the Part B deductible.
• Plan F (only for those eligible before 2020) is the most comprehensive.

For a full side-by-side chart, Medicare.gov keeps an official comparison you can read anytime.

A quick note about New York

New York is one of a handful of states with special rules that make Medigap easier to get. In New York, insurers must offer Medigap year-round on a "guaranteed issue" basis, meaning they can't turn you down or charge you more because of health problems. Not every state works this way, so if you move here from elsewhere — or leave — the rules can change.

This is one reason it's worth talking to your local State Health Insurance Assistance Program (SHIP), called HIICAP in New York, before making changes.

Common mistakes to avoid

A few Medigap missteps come up again and again:

1. Missing your open enrollment window. Your best chance to buy any Medigap plan without medical underwriting is the six-month period that starts when you're 65 or older AND enrolled in Part B. In New York, protections are broader, but the timing still matters. 2. Assuming Medigap covers drugs. It doesn't. You'll want a Part D plan separately. For 2026, Part D has a $2,100 out-of-pocket cap and a maximum deductible of $615. 3. Confusing Medigap with Medicare Advantage. They're different products with different rules. You can't have both at the same time. 4. Chasing the lowest price without checking rate history. Since benefits are standardized, price differences come down to the insurer. Ask how often they've raised rates in past years.