What is Medicare Supplement (Medigap) Insurance?

A Medicare Supplement insurance policy, also known as Medigap, is sold by private insurance companies to help pay for healthcare costs that Original Medicare doesn't cover — like copayments, coinsurance, and deductibles.

What Medigap Covers

Medigap policies help pay for: Medicare Part A coinsurance and hospital costs, Medicare Part B coinsurance or copayment, blood (first 3 pints), Part A hospice care coinsurance or copayment, skilled nursing facility care coinsurance, and — depending on the plan — foreign travel emergency care.

Standardized Plans

In most states, Medigap policies are standardized as Plans A through N. Each plan offers a different combination of benefits. The benefits in any Medigap plan are the same, regardless of which insurance company sells it — but premiums vary by company.

Key Advantages of Medigap

• Predictable costs — no surprise bills
• No network restrictions — see any doctor that accepts Medicare, nationwide
• No referrals needed to see specialists
• Ideal for frequent healthcare users or travelers
• Guaranteed renewable — the plan can't be cancelled as long as you pay premiums

Important: Medigap Open Enrollment

The best time to buy a Medigap policy is during your 6-month Medigap Open Enrollment Period, which starts when you're 65 or older and enrolled in Part B. During this window, you have a guaranteed right to buy any Medigap policy sold in your state — regardless of health conditions. After this window, insurers may use medical underwriting.