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What is Medigap (Medicare Supplemental) insurance?

En español | Medigap is also sometimes referred to as a Medicare supplemental insurance. A Medigap policy, sold by private insurance companies, can help pay some of the health care costs (“gaps”) Original Medicare doesn’t cover, such as Medicare deductibles, coinsurance and some extra benefits such as care when you travel outside the U.S. You have a one-time six-month Medigap open enrollment period that starts the first month you're 65 and enrolled in Part B. This period gives you a guaranteed right to buy any Medigap policy sold in your state regardless of your health status.

If you have Original Medicare and you buy a Medigap policy, Medicare will pay its share of the Medicare-approved amount for covered health care costs first. Then your Medigap policy pays its share of covered benefits. Every Medigap policy must follow federal and state laws designed to protect you, and it must be clearly identified as Medicare supplemental insurance. Insurance companies that sell Medigap can only sell you “standardized” Medigap policies, identified in most states by letters.

All Medigap plans offer the same basic benefits but some offer additional benefits.  Plans identified by the same letter cover the same benefits regardless of what company sells it.

Note: In Massachusetts, Minnesota and Wisconsin, Medigap policies may be standardized in a different way.

Note: Types of coverage that are NOT Medigap plans are Medicare Advantage plans, Medicare prescription drug plans, employer or union plans, including Federal Employees Health Benefits Program (FEHBP), TRICARE, veterans benefits and long term care insurance.

Here are some other things to remember about Medigap policies:

- You must have both Part A and Part B of Original Medicare

- You pay a monthly premium for your Medigap policy in addition to your Medicare premiums

- A Medigap policy covers one person; spouses must buy separate policies

- If you drop your Medigap policy, you might not be able to get it back

- If you have a Medicare Advantage plan, it’s illegal for anyone to sell you a Medigap policy unless you’re switching back to Original Medicare.



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