coinsurance

American  

[koh-in-shoor-uhns, -shur-] / ˌkoʊ ɪnˈʃʊər əns, -ˈʃɜr- /

noun

1. insurance underwritten jointly with another or others.

2. a form of property insurance in which an insurer assumes liability only for that proportion of a loss which the amount of insurance bears to a specified percentage of the value of the property.

3. 1. a form of health insurance in which the insured party contributes a specified percentage of the total cost of medical expenses after a deductible has been reached.

   2. the percentage contributed by the insured party.

      My coinsurance is 20%.

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coinsurance British  

/ -ˈʃɔː-, ˌkəʊɪnˈʃʊərəns /

noun

1. a method of insurance by which property is insured for a certain percentage of its value by a commercial insurance policy while the owner assumes liability for the remainder

2. joint insurance held by two or more persons

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Etymology

Origin of coinsurance

First recorded in 1885–90; co- + insurance

Example Sentences

That includes copayments, coinsurance, and deductibles but excludes monthly premium costs.

From Barron's • Mar. 5, 2026

Money in HSA accounts can be used toward the plan’s deductible, coinsurance, copayments, and for non-covered costs such as eyeglasses.

From Barron's • Nov. 24, 2025

The health plan could waive the coinsurance if the employee agrees to pay for the drug directly with the HRA account.

From The Wall Street Journal • Nov. 13, 2025

But Medicare Advantage is designed to have fixed copays like $30 for a specialist visit and 20% coinsurance for procedures.

From MarketWatch • Oct. 29, 2025

This bill would require that patients pay coinsurance rates based on a drug's negotiated, discounted price, rather than on its full list price.

From Salon • Nov. 22, 2024