Medicare Supplement

Understanding Medigap: What the Plan Letters Really Mean

If you live in Marion and you're new to Medicare — or helping a parent sort it out — the alphabet soup can feel overwhelming. Original Medicare, Part D, Medicare Advantage, and then something called Medigap with plans labeled A, B, C, D, F, G, K, L, M, and N. What do those letters mean, and why do they matter?

Making sense of Medigap in Marion

Here's the short version: Medigap (also called Medicare Supplement Insurance) is a private policy that helps pay some of the costs Original Medicare leaves behind. The letters aren't grades. They're standardized labels that describe what the plan covers.

What Medigap actually does

Original Medicare — Part A (hospital) and Part B (doctor and outpatient) — pays most of your covered care, but not all of it. You're still responsible for deductibles, coinsurance, and copays. Those can add up, especially after a hospital stay or a long stretch of outpatient treatment.

A Medigap policy works alongside Original Medicare. When Medicare pays its share, your Medigap plan picks up some or all of what's left, depending on the letter you chose. You pay a monthly premium to the private insurance company for that coverage.

A few key points to keep in mind:

• Medigap only works with Original Medicare. If you're on a Medicare Advantage plan, you can't use a Medigap policy at the same time.
• Medigap does not include prescription drug coverage. For that, you'd add a stand-alone Part D plan.
• Medigap doesn't typically cover dental, vision, hearing aids, or long-term care.

Why the letters are standardized

Here's the part that trips people up. In most states, including Indiana, Medigap plans are standardized by the federal government. That means a Plan G sold by one insurance company has to cover the exact same core benefits as a Plan G sold by any other company.

So if Company A and Company B both sell Plan N, the benefits are identical by law. What can differ is:

• The monthly premium
• The company's customer service and reputation
• How the company sets future rate increases
• Small extras some insurers add on

That's why comparing Medigap plans is really a two-step process: first pick the letter that matches the coverage level you want, then compare prices and companies for that letter.

A quick tour of the letters

You don't need to memorize every plan, but here's how to think about the lineup:

• Plans A and B offer the most basic benefits.
• Plans K, L, and M share more of the costs with you in exchange for lower premiums.
• Plan N covers a lot but leaves some smaller copays for office and ER visits.
• Plan G is one of the more comprehensive options available to new enrollees today.
• Plans C and F cover the Part B deductible, but they are only available to people who became eligible for Medicare before January 1, 2020. If you aged in after that date, those two are off the table.

For an official side-by-side chart, Medicare.gov has one at medicare.gov/health-drug-plans/medigap.

Timing matters more than most people realize

The best window to buy a Medigap policy is your Medigap Open Enrollment Period — the six months that start the month you're 65 or older and enrolled in Part B. During this window, companies can't turn you down or charge you more because of your health history.

Miss that window, and in most cases insurers can use medical underwriting. That means they can ask health questions and, depending on your answers, deny coverage or charge higher premiums. Indiana has some limited protections, but they don't replace that first six-month window.

This is different from the fall Annual Enrollment Period (October 15 – December 7), which is for Medicare Advantage and Part D — not Medigap. Medigap has its own timeline tied to when you enroll in Part B.

How Medigap fits with the rest of Medicare

Marion is in Grant County, where residents choosing Original Medicare often pair it with both a Medigap plan and a stand-alone Part D drug plan. That combination gives predictable costs for medical care plus prescription coverage.

A couple of 2026 program facts worth knowing if you go this route:

• Part D will have a $2,100 out-of-pocket cap on covered drugs in 2026.
• The Part D maximum deductible is $615 for 2026.
• The old coverage gap (the "donut hole") is gone as of 2025.
• If you'd rather spread drug costs across the year, the Medicare Prescription Payment Plan lets you pay monthly instead of all at once at the pharmacy.
• Higher-income enrollees may pay IRMAA surcharges on Part B and Part D — those begin above $109,000 in income for a single filer in 2026.