Medicare Supplement

Medigap Plan Letters, Explained for Eagle Pass Readers

EAGLE PASS, Texas — If you have Original Medicare (Part A and Part B), you know it doesn't pay for everything. There are deductibles, coinsurance, and copays that can add up. A Medicare Supplement policy — usually called Medigap — is private insurance you can buy to help pay some of those leftover costs.

What Medigap actually does

Medigap works alongside Original Medicare. Medicare pays its share of an approved bill first, then your Medigap policy pays part or all of what's left, depending on the plan you picked. It does not cover prescription drugs (you'd add a separate Part D plan for that), and it does not work with Medicare Advantage.

Why the plans are labeled with letters

Here's where a lot of people in Eagle Pass get tripped up: Medigap plans are sold by private insurance companies, but the benefits are standardized by the federal government. That means Plan G from one company covers the exact same medical costs as Plan G from another company. The price and customer service can differ — the benefits cannot.

The plans are identified by letters: A, B, C, D, F, G, K, L, M, and N. (Plans C and F are only available if you were eligible for Medicare before January 1, 2020.) Each letter is a different mix of benefits. Some cover almost everything Original Medicare leaves behind. Others cover less in exchange for a lower premium.

What the letters generally cover

Every lettered plan covers a core set of basics, like your Part A hospital coinsurance and an extra 365 days of hospital coverage after Medicare runs out. From there, the plans branch out:

• Some help with the Part A deductible, skilled nursing coinsurance, or hospice coinsurance.
• Some help with the Part B deductible (only older C and F plans do this now).
• Some pay for foreign travel emergency care up to plan limits.
• Plans K and L have yearly out-of-pocket limits and pay a percentage of covered costs, not the full amount.
• Plan N has small copays for some office and emergency room visits.

For a side-by-side chart of what each letter covers, the official source is medicare.gov.

The mistake to avoid: waiting past your open enrollment window

This is the piece worth reading twice. Your Medigap Open Enrollment Period is a one-time, six-month window that starts the month you're 65 or older AND enrolled in Part B. During that window, insurers must sell you any Medigap plan they offer at their best available rate, regardless of your health history.

Miss it, and in most states — Texas included — insurers can use medical underwriting. That means they can ask health questions, charge you more, or turn you down. People in Eagle Pass sometimes assume they can switch Medigap plans anytime the way they switch Advantage plans during the fall Annual Enrollment Period (Oct. 15 – Dec. 7). That is not how Medigap works. The AEP and the Medicare Advantage Open Enrollment Period (Jan. 1 – March 31) apply to Advantage and Part D — not Medigap.

Medigap vs. Medicare Advantage — pick one lane

You cannot have both a Medigap policy and a Medicare Advantage plan at the same time. Medigap is designed to pair with Original Medicare. Medicare Advantage (Part C) is a different way of getting your Medicare benefits, usually through an HMO or PPO network.

Eagle Pass is in Maverick County, where residents have a range of Medicare Advantage and Part D plans to choose from during the fall enrollment window. If you go the Original Medicare + Medigap + Part D route instead, the Medigap decision is separate from that annual shopping cycle — and, again, easier to make during your one-time open enrollment window.

A few 2026 numbers worth knowing

Even if you stick with Original Medicare and add a Medigap policy, you'll likely also want a stand-alone Part D drug plan. For 2026:

• Part D has a new $2,100 out-of-pocket cap on covered drugs.
• The Part D maximum deductible is $615.
• The old "donut hole" coverage gap is gone as of 2025 — Part D now has three phases.
• The Medicare Prescription Payment Plan lets you spread drug costs across monthly payments if you'd rather not pay a big bill at the pharmacy counter.
• IRMAA income-based surcharges on Part B and Part D start above $109,000 for a single filer in 2026.