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Medicare 101

Define Medigap

Christian Worstell

by Christian Worstell | Published October 26, 2023 | Reviewed by John Krahnert

Medicare Supplement Insurance (also known as Medigap) is Private health insurance that can help pay some of the cost-sharing expenses left behind by Original Medicare.

Medigap Eligibility Requirements

To be eligible for a Medigap plan:

  • You must be age 65 or older and enrolled in Medicare Part B.
  • You can't have a Medicare Advantage or Medicare Medical Savings Account (MSA) Plan

In some states, there are laws requiring insurance companies to sell Medigap plans to Medicare beneficiaries under 65, but federal law doesn't require it.

When Can You Buy a Medigap Plan?

The best time to buy a Medigap policy is when you first become eligible, during your 6-month Open Enrollment Period (OEP), which begins the day you are both 65 or older and enrolled in Medicare Part B. During your OEP, insurance carriers must allow you to enroll in any plan you choose, regardless of medical history or pre-existing conditions. But keep in mind: once your open enrollment window passes, you may be subject to medical underwriting or be denied coverage altogether.

The same OEP applies to all beneficiaries, so if you're younger than 65 and covered under Medicare because of a disability, you may not be able to purchase the policy you want (or any policy for that matter) until you turn 65.

How It Works

Medicare Part A and Part B cover various hospital and medical services, but beneficiaries are generally responsible for paying cost-sharing expenses such as deductibles, coinsurance, and copayments. A Medigap plan can help cover these, along with other benefits not covered by Medicare, such as extended hospitalization costs, skilled nursing facility care, and medical care outside of the U.S.

If you have a Medigap policy, Medicare will pay its share of covered health costs first, and then your Medigap policy will pay its share. 

Medigap Plan Comparison

Insurance companies can only sell "standardized" Medigap policies, meaning companies must offer same basic benefits for same-type policies. It's important to compare policies between companies because costs can vary widely, even for the same benefits. 

In most states, there are 10 different plan options to choose from. Each plan type is identified by a letter of the alphabet, and each covers a different variation of health care costs left by Original Medicare. The following chart enables you to compare the 10 standardized and defined Medigap plans side by side. 

Click here to view enlarged chart

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Medicare Supplement Benefits

Part A coinsurance and hospital coverage

Part B coinsurance or copayment

Part A hospice care coinsurance or copayment

First 3 pints of blood

Skilled nursing facility coinsurance

Part A deductible

Part B deductible

Part B excess charges

Foreign travel emergency

Medicare Supplement Benefits A B C* D F1* G1 K2 L3 M N4
Part A coinsurance and hospital coverage
Part B coinsurance or copayment 50% 75%
Part A hospice care coinsurance or copayment 50% 75%
First 3 pints of blood 50% 75%
Skilled nursing facility coinsurance 50% 75%
Part A deductible 50% 75% 50%
Part B deductible
Part B excess charges
Foreign travel emergency 80% 80% 80% 80% 80% 80%

* Plan F and Plan C are not available to Medicare beneficiaries who became eligible for Medicare on or after January 1, 2020. If you became eligible for Medicare before 2020, you may still be able to enroll in Plan F or Plan C as long as they are available in your area.

For more information on Medigap policies, visit us online to get your free quote. If you have questions about which Medigap policy is right for you, give us a call. Our agents are based in the United States and can help you find the right plan in your area. Call 1-800-995-4219 today to speak to a licensed agent, or read through some of our guides to learn more about Medicare and Medigap.

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