Medicare Supplement

Medigap Plan Letters Explained: Avoid a Costly Mix-Up

GEORGETOWN, Ky. — If you've started shopping for a Medicare Supplement policy, you've probably noticed the plans go by single letters: Plan A, Plan G, Plan N, and so on. It looks confusing, but there's a helpful secret hiding in those letters. They are standardized by federal law, which means Plan G from one insurance company covers the exact same things as Plan G from another company.

The letters on Medigap plans aren't random — they matter

That standardization is designed to protect you. Once you understand how the letters work, comparing Medigap options becomes much simpler — and you're less likely to make a mistake you'll regret later.

What a Medigap policy actually does

A Medigap policy (also called Medicare Supplement Insurance) works alongside Original Medicare — Part A (hospital) and Part B (medical). Original Medicare pays its share of covered services, and then your Medigap policy helps pay some of the leftover costs, like coinsurance, copayments, and deductibles.

A few important things to know:

• Medigap only works with Original Medicare. You cannot use a Medigap policy if you're enrolled in a Medicare Advantage plan.
• Medigap does not include prescription drug coverage. For drugs, you'd add a separate Part D plan.
• You pay a monthly premium to the insurance company for a Medigap policy, on top of your Part B premium.

How the standardized letters work

In most states, Medigap plans are sold using ten standardized letters: A, B, C, D, F, G, K, L, M, and N. (Massachusetts, Minnesota, and Wisconsin standardize their plans differently.) Each letter represents a specific set of benefits set by Medicare.

Here's the key point: the benefits inside each letter are identical from company to company. A Plan G sold by one insurer covers the same gaps as a Plan G sold by another. What can differ is the price, the customer service, and any small extras the company adds on.

There are also two versions of some plans — a standard version and a high-deductible version — so read the fine print before you sign.

The Plan F and Plan C rule (this trips people up)

Here's a detail worth knowing, because it's a common source of confusion: Plans C and F are only available to people who became eligible for Medicare before January 1, 2020. If you turned 65 or otherwise became Medicare-eligible on or after that date, you can't buy Plan C or Plan F as a new customer, even though you may see them advertised.

If a friend or family member tells you they have Plan F and love it, that's fine — but check your own eligibility date before assuming it's an option for you.

The best time to enroll — and why timing matters

Your Medigap Open Enrollment Period is a one-time, six-month window that begins 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 at their best available rate, and they can't turn you down or charge you more because of health problems.

Miss that window, and in most states insurers can use medical underwriting — meaning they can ask about your health, charge more, or decline to cover you. That's why Medigap timing is one of the most important choices new Medicare enrollees face.

Georgetown, Ky.: where to get local help

Georgetown is in Scott County, where residents have access to Original Medicare plus a range of Medicare Advantage and Part D options offered at the county level. Because Medigap policies are sold by private insurers and regulated in part by the state, availability and pricing in Kentucky can differ from a neighboring state.

For unbiased, personalized help, Kentuckians can contact the Kentucky State Health Insurance Assistance Program (SHIP), which offers free one-on-one counseling. You can also compare Medigap policies available in your ZIP code using the official tool at medicare.gov.