Original Medicare Part A and Part B may require you to pay coinsurance for services and supplies. Without an annual limit to out-of-pocket costs, an unexpected medical event could cost you more than your budget allows. To help lower out-of-pocket costs, you can purchase a Medicare Supplement policy. Also known as Medigap or “Med Supp,” Medicare Supplement helps cover the costs that Original Medicare does not, including deductibles, copayments, coinsurance, and medical care while traveling outside of the United States.

Types of Plans

Medigap policies are sold by private insurance companies, and are standardized and regulated by the federal government. They are identified by letters A-N, and you will pay a monthly premium for the coverage. Costs can vary between the same Medigap plan from different companies, even in the same state. Some plans offering more benefits in exchange for a higher premium.


Most people choose to enroll in a Medicare Supplement plan when they are first eligible. You will have an initial Medigap Open Enrollment Period. During this 6-month period that starts when you are 65 years old and enrolled in Medicare Part B, you can buy any Medigap plan sold in your state without medical underwriting. In other words, you cannot be turned down or charged more due to pre-existing conditions during this period. If you choose not to enroll in a Medigap plan when you are first eligible, you will not have a guaranteed issue right to join one.