Medicare Supplement

Why Medigap letters mean the same benefits in Zionsville

ZIONSVILLE, Ind. — If you're new to Medicare or helping a parent sort through the mail piling up on the kitchen counter, you've probably seen the words "Medicare Supplement" or "Medigap." They sound alike because they are the same thing. And once you understand what Medigap does — and what those letter names mean — the whole system gets a lot easier to read.

Here's a plain-language guide to how Medigap works in 2026.

What Medigap actually is

Medigap is private insurance you can buy to help pay some of the costs Original Medicare (Part A and Part B) leaves behind. Those leftover costs include things like the Part A hospital deductible, the Part B 20% coinsurance, and certain hospital costs after Medicare's own days run out.

Medigap does not replace Medicare. It works alongside it. Medicare pays its share first, and then your Medigap policy pays some or all of what's left, depending on which plan you chose.

A few important ground rules from Medicare.gov:

• You must be enrolled in Part A and Part B to buy a Medigap policy.
• Medigap only works with Original Medicare. You cannot use it with a Medicare Advantage plan.
• Medigap policies generally don't include prescription drug coverage. For drugs, most people add a separate Part D plan.
• Each Medigap policy covers one person. Spouses need their own policies.

How the letter names work

This is the part that trips people up. Medigap plans are sold by private companies, but the benefits inside each "letter" plan are standardized by the federal government. That means Plan G from one insurance company has to cover the same core benefits as Plan G from another company.

The plans currently sold to new enrollees are labeled with letters: A, B, D, G, K, L, M, and N. (Plans C and F are no longer available to people who became eligible for Medicare on or after January 1, 2020, because of a federal law change. If you were eligible before that date, you may still be able to buy them.)

Because benefits are standardized, the main things that differ between two companies selling the same letter plan are:

• The monthly premium
• Customer service and billing
• Optional extras a few carriers add on

Massachusetts, Minnesota, and Wisconsin standardize their Medigap plans differently, but Indiana follows the standard federal letters.

What Medigap does not cover

Medigap is designed to fill gaps in Original Medicare — not to be a full benefits package. In general, Medigap policies do not cover:

• Prescription drugs (you'd add a Part D plan for that)
• Routine dental, vision, or hearing care
• Long-term custodial care in a nursing home
• Private-duty nursing
• Eyeglasses or hearing aids

If those services matter to you, it's worth knowing up front so you can plan for them separately.

Why timing matters so much

The single most important thing to know about Medigap is your Medigap Open Enrollment Period. This is a six-month window that starts the month you're 65 or older and enrolled in Part B. During that window, insurance companies must sell you any Medigap policy they offer at the best available rate, and they can't turn you down or charge you more because of your health.

Outside that window, in most states — Indiana included — insurance companies can use medical underwriting. That means they can ask about your health history and decide whether to sell you a policy and at what price. Missing that first six-month window is one of the more expensive mistakes people make on Medicare, so it's worth putting on the calendar.

How this fits with the rest of Medicare in 2026

Medigap is one of two main paths people take. The other is Medicare Advantage (Part C), which bundles Part A, Part B, and usually Part D into one private plan with its own network and rules. You generally cannot have both a Medigap policy and a Medicare Advantage plan.

Zionsville is in Boone County, where — as in the rest of Indiana — residents can shop Medicare Advantage and Part D plans during the Annual Enrollment Period, October 15 through December 7. Medicare Advantage members also have the Medicare Advantage Open Enrollment Period from January 1 through March 31 to make one switch. Medigap, by contrast, isn't tied to those annual windows — you can apply any time, but outside your initial window, approval isn't guaranteed.

A few other 2026 program facts worth knowing while you're weighing your options:

• Part D now has an out-of-pocket cap of $2,100 for covered drugs.
• The Part D deductible maximum is $615.
• The old "donut hole" coverage gap was eliminated in 2025; Part D now has three simpler phases.
• The Medicare Prescription Payment Plan lets you spread your drug costs across the year in monthly amounts instead of paying all at once at the pharmacy.
• IRMAA — an income-based surcharge on Part B and Part D — kicks in above $109,000 in income for a single filer in 2026.