Medicare Supplement

How Medigap's standardized letters work in Gilbert

GILBERT, Ariz. — If you've ever tried to compare Medicare Supplement plans and felt lost in a sea of letters — Plan A, Plan G, Plan N — you're not alone. Those letters aren't random. They're part of a standardized system that, once you understand it, makes shopping for coverage a lot less stressful.

Making sense of Medigap in Gilbert

Here in Gilbert, where thousands of residents are aging into Medicare each year, Medigap is one of the most common questions local seniors bring to their SHIP counselors. Let's walk through what these plans do and why the letters matter.

What Medigap actually does

Medicare Supplement Insurance — usually called Medigap — is private insurance you can buy to help pay some of the costs Original Medicare (Parts A and B) leaves behind. Think coinsurance, copayments, and hospital deductibles.

Medigap does not replace Medicare. It works alongside it. When you go to the doctor, Original Medicare pays its share first, and your Medigap plan picks up some or all of the rest, depending on which plan you chose.

A few important ground rules from Medicare.gov:

• You must have both 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 does not include prescription drug coverage. For that, you'd add a separate Part D plan.
• Each Medigap policy covers one person. Spouses need their own policies.

Why the letters exist

Before the plans were standardized, comparing Medigap policies was a mess. Every insurance company sold something different, and it was nearly impossible to tell one plan from another.

Today, in most states — including Arizona — Medigap plans are standardized by the federal government and labeled with letters: A, B, C, D, F, G, K, L, M, and N. (Massachusetts, Minnesota, and Wisconsin do things a little differently.)

Here's the key idea: a plan with the same letter offers the same basic benefits, no matter which insurance company sells it. A Plan G from one carrier covers the same core items as a Plan G from another. What can differ is the price and the customer service you get.

That means when you're shopping, you can focus on two things: which letter fits your needs, and which company offers a fair price with good service.

A quick tour of the letters

Every standardized Medigap plan covers a set of basics, such as Part A hospital coinsurance. From there, the letters build up different levels of coverage:

• Plans A and B cover the fewest extras.
• Plans K, L, and M share costs with you, often with a lower monthly premium in exchange.
• Plan N covers most gaps but asks for small copays at doctor and ER visits.
• Plan G is one of the most comprehensive plans available to people newly eligible today.
• Plans C and F are only available to people who became eligible for Medicare before January 1, 2020. If you turned 65 after that date, you can't buy them.

There's no single "right" letter. The best fit depends on how often you see doctors, how you feel about paying more up front versus more at the pharmacy or clinic, and your budget.

When you can buy — and why timing matters

The best time to buy a Medigap policy is during your Medigap Open Enrollment Period. This is a one-time, six-month window that starts the month you're 65 or older and enrolled in Part B.

During this window:

• Insurance companies must sell you any Medigap policy they offer.
• They can't charge you more because of health problems.
• They can't make you wait for coverage of a pre-existing condition (in most cases).

Miss this window, and in many situations insurers can use medical underwriting — meaning they can charge more or turn you down based on your health. That's why local SHIP counselors often tell Gilbert residents: mark this window on your calendar.

What this looks like in Maricopa County

Gilbert is in Maricopa County, where residents have access to a wide range of Medicare options — Original Medicare with or without a Medigap policy, Medicare Advantage plans, and standalone Part D drug plans. Because Medigap availability and pricing are regulated at the state level, Arizona residents generally see the same set of standardized letters sold here as elsewhere in the country.

If you're weighing Medigap versus Medicare Advantage, that's a separate decision worth talking through carefully. The two work very differently, and switching between them later isn't always simple.

A few 2026 Medicare facts worth knowing

Even though Medigap doesn't cover prescriptions, most people who choose it also enroll in a Part D drug plan. For 2026:

• The Part D out-of-pocket cap is $2,100. Once you hit that, you pay $0 for covered drugs the rest of the year.
• The Part D maximum deductible is $615.
• The old "donut hole" is gone — Part D now has three simpler phases.
• The Medicare Prescription Payment Plan lets you spread drug costs across the year in monthly installments.
• IRMAA surcharges on Part B and Part D begin above $109,000 in income for single filers.

Key dates: Annual Enrollment runs October 15 – December 7, and Medicare Advantage Open Enrollment runs January 1 – March 31.