Medicare Supplement

What Medigap's Lettered Plans Really Mean in 2026

GRESHAM, Ore. — If you've ever tried to compare Medicare Supplement policies and felt like you were staring at alphabet soup, you're not alone. Plans labeled A, B, D, G, K, L, M, and N sound like a code — but there's a reason behind those letters, and understanding them can make your Medicare decisions a lot less stressful.

Here's a plain-language guide to how Medigap works, what those letters mean, and why the system is set up the way it is.

What Medigap actually does

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

If you have Original Medicare and a Medigap policy, Medicare pays its share of the approved amount first, and then your Medigap plan pays its share. You still pay a monthly premium for the Medigap policy, in addition to your Part B premium.

One important note: Medigap is different from Medicare Advantage (Part C). You can't have both at the same time. Medigap only works with Original Medicare.

Why the letters exist

Back in 1990, federal law standardized Medigap policies so shoppers wouldn't have to compare hundreds of confusing, one-of-a-kind products. Since then, every Medigap policy sold in most states must fit into one of a set number of standardized "lettered" plans.

That means Plan G from one insurance company covers the exact same benefits as Plan G from another company. The price and customer service may differ, but the benefits within each letter are identical by law.

Three states — Massachusetts, Minnesota, and Wisconsin — standardize their Medigap plans differently. Oregon, however, uses the standard federal lettering system, so shoppers in Gresham see the same plan letters as most of the country.

What the letters cover

Each lettered plan offers a different mix of benefits. According to Medicare.gov, here's the general idea:

• Plans A and B cover the basics, like Part A hospital coinsurance and Part B coinsurance.
• Plans D, G, M, and N offer broader coverage, including skilled nursing coinsurance and foreign travel emergency care (up to plan limits).
• Plans K and L have lower premiums in exchange for cost-sharing — you pay a percentage of certain services until you reach an annual out-of-pocket limit.
• Plan N typically has small copays for some office and emergency visits.

A key change to know: Plans C and F, which covered the Part B deductible, are no longer sold to people who became eligible for Medicare on or after January 1, 2020. If you were eligible before that date, you may still be able to buy them.

When you can buy a Medigap policy

The best time to buy Medigap is during your Medigap Open Enrollment Period — the six-month window that starts the month you're 65 or older and enrolled in Part B. During this window, insurers can't turn you down or charge you more because of health conditions.

Outside that window, in most states, insurers can use medical underwriting, which means they can look at your health history and potentially deny coverage or raise your premium. That's why timing matters so much.

How Medigap fits with Part D and 2026 changes

Medigap policies sold today don't include prescription drug coverage. If you want help paying for prescriptions, you'd typically add a stand-alone Part D plan.

Part D has some notable updates for 2026 worth knowing:

• The annual out-of-pocket cap on covered drugs is $2,100.
• The maximum Part D deductible is $615.
• The old "donut hole" coverage gap has been eliminated as of 2025 — there are now three coverage phases instead of four.
• The Medicare Prescription Payment Plan lets you spread drug costs across the calendar year in monthly payments, at no extra charge.
• IRMAA surcharges (higher premiums for higher incomes) begin above $109,000 for a single filer in 2026.

Local context for Gresham

Gresham is in Multnomah County, where residents have access to Original Medicare plus the Medigap and Part D options available statewide. Medigap availability in Oregon is regulated at the state level, and licensed insurers must offer at least Plan A if they sell any Medigap plans.

If you're weighing Medigap versus Medicare Advantage, remember they're different paths — Medigap pairs with Original Medicare and a separate drug plan, while Medicare Advantage bundles coverage through a private plan.