A Medigap (Medicare Supplement) policy is a private health insurance that helps supplement Original Medicare. This means it helps pay some of the health care costs that Original Medicare doesn’t cover (like copayments, coinsurance, and deductibles).
If you have Original Medicare and a Medigap policy, Medicare will pay its share of the Medicare-approved amounts for covered health care costs. Then your Medigap policy pays its share.
All Medigap policies must follow federal and state laws designed to protect you, and policies must be clearly identified as “Medicare Supplement Insurance”. Medigap insurance companies can only sell you a “standardized” Medigap policy and they must offer the same basic benefits, no matter which insurance company sells it.