Medicare Supplement

Which Medigap Letters Can Chattanooga Buyers Choose?

Medigap — also called Medicare Supplement Insurance — is a private policy that helps pay some of the out-of-pocket costs Original Medicare leaves behind, like coinsurance and copays. It rides alongside Medicare Parts A and B. It does not replace them, and it is not the same thing as a Medicare Advantage plan.

What Medigap is, and what it is not

If you live in Chattanooga and have Original Medicare, a Medigap policy can help make your costs more predictable. But Medigap does not cover prescription drugs, so most people also enroll in a stand-alone Part D plan.

The standardized plan letters you can buy in Tennessee

Medigap is federally standardized in most states, including Tennessee. That means a Plan G sold by one insurer covers the same core benefits as a Plan G sold by another. The difference between carriers usually comes down to price, customer service and how the company handles rate changes over time.

For anyone newly eligible for Medicare today, these letters are available in Tennessee:

• Plan A, Plan B — the more basic options.
• Plan D, Plan G, Plan G-HD (high deductible), Plan M, Plan N — mid-range and popular choices, with Plan G often discussed for people who want broad coverage.
• Plan K, Plan L — cost-sharing plans with lower premiums and higher out-of-pocket limits.

Plan C and Plan F are only available to people who became eligible for Medicare before January 1, 2020. If you were eligible before that date and never enrolled, you may still be able to buy them.

Massachusetts, Minnesota and Wisconsin standardize Medigap differently. Tennessee follows the federal letters, so the list above is what you will see in Chattanooga.

How Medigap pairs with Original Medicare and Part D

Here is the typical setup for a Chattanooga resident using Medigap:

1. Original Medicare (Part A and Part B) pays first for hospital and medical services. 2. Your Medigap plan then pays its share of the leftover coinsurance, copays and — depending on the letter — the Part A or Part B deductible. 3. A stand-alone Part D plan covers your prescription drugs.

For 2026, Part D has a $2,100 out-of-pocket cap and a maximum deductible of $615. The old coverage gap (the "donut hole") was eliminated in 2025, so Part D now has three phases instead of four. If drug costs are hard to manage month to month, ask your Part D plan about the Medicare Prescription Payment Plan, which smooths those costs over the year.

Higher-income enrollees may also pay an IRMAA surcharge on Part B and Part D; for 2026 that begins above $109,000 in income for a single filer.

Insurers selling Medigap in Tennessee

Chattanooga is in Hamilton County, and Medigap availability is set at the state level, not the county level. So the same list of insurers approved to sell Medigap in Tennessee is available to Chattanooga residents.

The table below lists every insurer approved to sell Medigap in Tennessee and which plan letters each one offers. You will see familiar names like AARP - UnitedHealthcare Insurance Company, BlueCross BlueShield of Tennessee, Mutual of Omaha (Omaha Supplemental Insurance Company), Humana (Humana Benefit Plan of Illinois, Inc.), State Farm Mutual Automobile Insurance Company and Farm Bureau Health Plans, along with many others. Not every insurer sells every letter — for example, some offer only Plans A, F, G and N, while others carry a wider range including high-deductible options.

Because benefits are standardized by letter, the practical shopping question is: among the insurers that sell the letter you want, which one fits your budget and how do they handle premium changes over time? The Tennessee Department of Commerce and Insurance publishes rate guides that can help you compare.

The rules that shape your choice in Tennessee

Two federal rules matter most:

• Medigap Open Enrollment Period. This is a one-time, six-month window that begins the month you are 65 or older and enrolled in Part B. During this window, you can buy any Medigap policy sold in Tennessee without answering health questions. This is the strongest protection you get.
• Guaranteed issue rights. Outside your open enrollment window, federal law still gives you a limited right to buy certain Medigap plans in specific situations — for example, if a Medicare Advantage plan leaves your area or you move out of its service area.

Outside those windows, insurers in Tennessee can use medical underwriting, which means they can review your health and decide whether to sell you a policy or at what price. Some states have extra protections like a "birthday rule"; Tennessee's specific rules on switching are best confirmed with the state insurance department or your local SHIP counselor before you make a change.

How to think through the decision

A few plain questions can narrow the field:

• Do you want the most predictable out-of-pocket costs, or are you comfortable trading a higher deductible for a lower premium?
• Do you travel? Some letters include foreign travel emergency benefits.
• Are you inside your six-month Medigap Open Enrollment Period? If so, your options are widest right now.
• Have you lined up a Part D drug plan? Medigap will not cover your prescriptions.

No one letter is right for everyone, and no one insurer is "best." The right answer depends on your health, your budget and how you like to handle bills.

Where to get unbiased help

• Medicare.gov — use the Medigap policy search to see plans and insurers in Tennessee.
• 1-800-MEDICARE — available 24/7 for general questions.
• Tennessee SHIP (State Health Insurance Assistance Program) — free, one-on-one counseling from trained volunteers who do not sell insurance.
• Tennessee Department of Commerce and Insurance — publishes Medigap rate comparison guides.

Also keep the calendar in mind: Medicare's Annual Enrollment Period runs October 15 – December 7, and Medicare Advantage Open Enrollment runs January 1 – March 31. Those windows apply to Advantage and Part D changes; Medigap has its own rules described above.