Supplemental Major Medical Insurance

Updated: 20 April 2026

What Does Supplemental Major Medical Insurance Mean?

Supplemental major medical insurance is a policy that covers expenses not included in a basic medical plan. It becomes effective once medical expenses exceed the coverage limit of the basic plan. Shoppers comparing health insurance plans often look at supplemental coverage as a way to protect against costs that go beyond the cap on a basic policy.

Insuranceopedia Explains Supplemental Major Medical Insurance

Typically, the insured individual’s basic health insurance reimburses covered expenses, usually without requiring a deductible. Once these expenses exceed the coverage limit, the supplementary policy covers a percentage of the amount above the corridor deductible, which is the deductible between the two plans. However, there is often a limit beyond which the policy reimburses medical expenses in full. Because the way a corridor deductible interacts with co-pays and coinsurance can get confusing, this breakdown of premiums, deductibles, co-pays, and coinsurance explains how each one works before a supplemental policy kicks in.