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  

/ ˌkəʊɪnˈʃʊərəns, -ˈʃɔː- /

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

See Examples For:

coinsurance

The estimate includes Medicare premiums, out-of-pocket prescription-drug costs and other medical expenses such as copayments, coinsurance and deductibles for doctor and hospital visits.

From MarketWatch ● Jul. 21, 2026

You will likely have health challenges; Medicare premiums, deductibles and coinsurance; emergency house repairs; and one or both of you may even require nursing-home care.

From MarketWatch ● Apr. 1, 2026

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

From Barron's ● Mar. 5, 2026

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

An employer could have a health plan that pays for expensive drugs with 20% employee coinsurance.

From The Wall Street Journal ● Nov. 13, 2025