Compare benefits offered by each Medigap plan including Plan A, Plan B, Plan C, and more., Medicare Supplement Insurance (Medigap) is extra insurance you can buy from a private insurance company to help pay your share of costs in Original Medicare., Medigap Medicare Supplement Insurance sold by private insurance companies to fill “gaps” in Original Medicare coverage., Original Medicare pays for many, but not all, health care services and supplies. Medicare Supplement Insurance (Medigap) is extra insurance you can buy from a private health insurance company to help pay your share of out-of-pocket costs in Original Medicare (Part A and Part B), like copayments, coinsurance, and deductibles., Health insurance companies must clearly identify a Medigap policy as "Medicare Supplement Insurance." Your best time to buy a policy is during your Medigap Open Enrollment Period. Follow these steps when you’re ready to buy a Medigap policy:, Learn about Medicare health plans, Medigap, how Medicare works with other insurance, and Drug coverage..