Medicare Supplement

Medicare Supplement Basics for Louisville Beneficiaries

LOUISVILLE, Ky. — If you're new to Medicare, you've probably heard the word "Medigap" tossed around at the kitchen table or in a friend's advice. Medicare Supplement insurance — the formal name for Medigap — is a type of private policy designed to help pay some of the out-of-pocket costs that Original Medicare (Part A and Part B) leaves behind, like coinsurance, copayments, and certain deductibles.

Medigap fills the gaps — but not the way many people think

Here's the part that trips people up: Medigap works with Original Medicare, not with a Medicare Advantage plan. And it doesn't add new benefits like dental, vision, hearing, or prescription drug coverage. It's a math helper for the bills Original Medicare doesn't finish paying.

How the standardized letters work

To make shopping less confusing, Medigap policies are standardized by the federal government. In most states, including Kentucky, they come in lettered plans: 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 idea: a Plan G from one company covers the same core benefits as a Plan G from another company. The letter tells you the benefits. What differs between companies is the monthly premium, customer service, and how they raise rates over time.

Three states — Massachusetts, Minnesota, and Wisconsin — standardize their Medigap plans differently, but Kentucky uses the standard federal letters.

What Medigap does not do

This is where mistakes happen, so read carefully:

• Medigap does not cover prescription drugs. For that, you need a separate Medicare Part D plan. In 2026, Part D has a $2,100 annual out-of-pocket cap on covered drugs and a maximum deductible of $615. The old "donut hole" coverage gap was eliminated in 2025, so Part D now has three phases instead of four.
• Medigap does not pair with Medicare Advantage. It's illegal for someone to sell you a Medigap policy if you're enrolled in a Medicare Advantage plan, unless you're switching back to Original Medicare.
• Medigap generally does not cover long-term care, most dental, vision, hearing aids, or private-duty nursing.
• Medigap covers one person per policy. Spouses each need their own.

The enrollment window that quietly matters most

The single most important date for Medigap isn't in October or December — it's your Medigap Open Enrollment Period. This is a one-time, six-month window that starts the month you're 65 and enrolled in Part B.

During those six months, insurance companies must sell you any Medigap policy they offer at the best available rate, regardless of your health history. Once that window closes, in most states insurers can use medical underwriting — meaning they can charge you more or turn you down based on your health. Kentucky follows the federal rule here; it does not require year-round guaranteed issue.

Missing that window is one of the most expensive mistakes new Medicare enrollees make.

Louisville-area context

Louisville sits in Jefferson County, where residents have a wide mix of Medicare choices, including Original Medicare paired with a Medigap policy and a stand-alone Part D drug plan, or Medicare Advantage plans that bundle coverage together. Plan availability is set at the county level by the Centers for Medicare & Medicaid Services (CMS), and Jefferson County typically offers dozens of Medicare Advantage and Part D options each year during the Annual Enrollment Period (Oct. 15 – Dec. 7).

Medigap is different — it's sold year-round by private insurers licensed in Kentucky, and it's not tied to the fall enrollment calendar.

A few common questions

Is Medigap the same as Medicare Advantage? No. Medicare Advantage (Part C) replaces the way you get your Original Medicare benefits and is offered by private companies. Medigap works alongside Original Medicare to help pay your share of the costs. You cannot have both at the same time.

Do I still need a Part D plan if I have Medigap? Yes, if you want prescription drug coverage. Medigap policies sold today do not include drug coverage. Going without creditable drug coverage can also trigger a late-enrollment penalty later.

Can I switch Medigap plans later? You can apply anytime, but outside your initial six-month Medigap Open Enrollment Period, insurers in Kentucky can generally use medical underwriting. That means a switch isn't guaranteed and could cost more based on your health.

Does income affect what I pay? Medigap premiums are set by the insurer, not by income. However, higher-income enrollees may pay IRMAA surcharges on Part B and Part D premiums — those begin above $109,000 in income for a single filer in 2026.

Where to get answers you can trust

Medigap is one of those decisions where a 20-minute conversation with a neutral counselor can save you years of frustration. Free, unbiased help is available:

• Medicare.gov — the official source for how each lettered plan works and a plan-finder tool.
• 1-800-MEDICARE (1-800-633-4227), available 24/7.
• Kentucky SHIP (State Health Insurance Assistance Program), which offers free one-on-one counseling to Louisville-area residents and can walk you through Medigap letters, Part D, and enrollment timing without trying to sell you anything.

Take your time, ask questions, and — if you're approaching 65 — mark that six-month Medigap window on your calendar. It's the door that only opens once.