coinsurance

noun

co·​in·​sur·​ance ˌkō-ən-ˈshu̇r-ən(t)s 

 also  -ˈin-ˌshu̇r-

1

: joint assumption of risk (as by two underwriters) with another

2

: insurance (such as fire insurance) in which the insured is obligated to maintain coverage on a risk at a stipulated percentage of its total value or in the event of loss suffer a penalty in proportion to the deficiency

3

: health insurance in which the insured is required to pay a fixed percentage of the cost of medical expenses after the deductible has been paid and the insurer pays the remaining expenses

Coinsurance is not a new idea—Americans who grew up in the era before managed care will remember their parents paying 20% of the costs of office visits, tests, and prescriptions.

—Thomas H. Lee et al.

Examples of coinsurance in a Sentence

Recent Examples on the Web

Pay attention to your out-of-pocket costs Open enrollment provides an opportunity for beneficiaries to manage how much their overall out-of-pocket costs — including premiums, deductibles and coinsurance — may increase in 2025. —Lorie Konish, CNBC, 3 Dec. 2024

Under the bill, the health insurance program would automatically cover all U.S. residents without deductibles, coinsurance or copayments. —Louis Jacobson and Maria Ramirez Uribe, Austin American-Statesman, 27 July 2024

Medicare Advantage plans typically combine coverage for hospital and outpatient care and prescriptions, while eliminating the 20% coinsurance requirement and capping customers' annual out-of-pocket costs. —Stephanie Armour, CBS News, 4 Nov. 2024

After a deductible is met, an insurance company usually pays a part of subsequent medical claims (known as coinsurance) until that maximum is reached. —Aria Bendix, NBC News, 30 Oct. 2024

Word History

First Known Use

circa 1889, in the meaning defined at sense 1

Medical Definition

coinsurance

noun

co·​in·​sur·​ance ˌkō-ən-ˈshu̇r-ən(t)s, -ˈshər- also -ˈin-ˌshu̇r-, -ˌshər- 

: health insurance in which an insurer requires the insured to pay a fixed percentage of the cost of medical expenses after the deductible has been paid and with the insurer to pay the remaining expenses

Coinsurance is not a new idea—Americans who grew up in the era before managed care will remember their parents paying 20% of the costs of office visits, tests, and prescriptions.

—Thomas H. Lee et al., The New England Journal of Medicine

Legal Definition

coinsurance

noun

co·​in·​sur·​ance ˌkō-in-ˈshu̇r-əns, kō-ˈin-ˌshu̇r- 

1

: joint assumption of risk (as by two underwriters) with another

2

: insurance (as fire insurance) in which the insured is obligated to maintain coverage on a risk at a stipulated percentage of its total value or in the event of loss to suffer a penalty in proportion to the deficiency