What it is
Medigap, also called Medicare Supplement insurance, is sold by private insurance companies to help with some costs Original Medicare does not pay on its own. These costs can include things like coinsurance, copayments, and deductibles. Medigap works alongside Original Medicare (Parts A and B), not in place of it.
The plan letters, such as A, B, C, D, F, G, K, L, M, and N, are labels for standardized benefit packages. In most states, a plan with a given letter offers the same basic benefits no matter which company sells it. Not every letter is available everywhere or to everyone, and some letters may no longer be open to new enrollees.
Some states, such as Massachusetts, Minnesota, and Wisconsin, organize Medigap differently and may not use the same letters. Because rules vary by state and change over time, it helps to confirm what is offered where you live.
How it’s traditionally been approached
Traditionally, people have approached Medigap by first looking at which benefits each letter includes, then comparing those side by side. Because the benefits are standardized, many people focus on how the plan fits their health needs and budget comfort rather than on differences in coverage between companies.
Some people choose a plan with broader benefits for more predictable out-of-pocket costs. Others choose a plan with fewer benefits in exchange for a different balance of cost and cost-sharing. Neither approach is right or wrong; it depends on personal circumstances and preferences.
Many people also compare Medigap with Medicare Advantage (Part C), which is a different way to receive Medicare benefits through a private plan. Medigap works with Original Medicare, while Medicare Advantage typically has its own network and rules. Some people weigh the two based on provider choice, travel, and how they like to manage costs.
How the right agent may help
An independent agent who works with Medicare Supplement plans may help you sort through the letters, explain how they differ, and show which ones are available in your state. A conversation is generally a chance to ask questions at your own pace, and an agent may also explain how Medigap compares with Medicare Advantage.
In a typical visit or call, an agent may ask about your current coverage, the doctors and hospitals you prefer, your prescription needs, and how you feel about cost-sharing. Because Medigap does not generally include drug coverage on its own, they may also explain how a separate drug plan fits in.
Good questions to ask include: Which letters are available to me? Does the timing of my enrollment affect my options? Do I need to answer health questions? How might rates change over time? Please verify plan details, networks, and drug formularies directly with the carrier, the official marketplace, or a licensed agent before enrolling.
The bigger picture
Choosing health coverage is not only a paperwork task; it can affect your peace of mind. Knowing what you might owe when you need care can ease worry, while confusion about plan options can add stress. Taking time to understand the letters may help you feel more settled about the decision.
Your overall wellbeing includes your finances, your health, and your sense of security. Some people find it helpful to talk with family, or with a Providers.plus listing for care providers, as they think about what matters most. Every approach has its place, and the best fit is a personal one.
Keep in mind
- Medigap rules, available plans, and enrollment rights vary by state and can change from year to year.
- This site is an independent, privately-run educational and referral directory, not affiliated with Medicare.gov, CMS, Social Security, or any government agency.
- Eligibility, coverage, and savings are never guaranteed, and this page does not offer legal, tax, financial, or government advice.
- Visit Medicare.gov for current enrollment dates and personalized information, and verify plan details with the carrier or a licensed agent before enrolling.
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Frequently asked questions
What do Medigap plan letters mean?
Medigap plan letters are labels for standardized benefit packages sold by private insurers to supplement Original Medicare. In most states, each letter offers the same basic benefits regardless of the company. Availability varies by state, so confirm what is offered where you live.
Are all Medigap plans with the same letter identical?
In most states, plans with the same letter offer the same core benefits, no matter which company sells them. What can differ is the company, customer service, and how rates are set. Always verify details with the carrier or a licensed agent before enrolling.
Can I still buy every Medigap plan letter?
Not necessarily. Some letters may not be open to new enrollees, and availability depends on your state and when you became eligible for Medicare. An independent agent or Medicare.gov may help you see what is currently offered.
Do Medigap plans cover prescription drugs?
Generally, no. Medigap is designed to help with certain Original Medicare cost-sharing, not with drug costs. Many people look at a separate Medicare drug plan, and an agent may explain how the pieces fit together.
Can I use Medigap with a Medicare Advantage plan?
Generally, Medigap is designed to work with Original Medicare, not alongside a Medicare Advantage plan. These are two different ways of receiving Medicare benefits. An agent may help you compare them, and you can confirm current rules at Medicare.gov.
How can an agent help me understand Medigap plan letters?
An independent agent may explain what each letter generally includes, narrow the options available in your state, and answer questions about enrollment timing. This is educational support, not a promise of any result. Always verify details before enrolling.
Educational resource. Government Health Plan shares general information and connects people with independent agents. It is not professional advice. Talk with a qualified professional about your own situation.