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

Plus, their out-of-pocket exposure (in terms of deductibles and coinsurance) is $18,900. —John C. Goodman, Forbes, 29 Feb. 2024

One law will prevent insurers and health maintenance organizations from imposing copayments, coinsurance or deductible requirements for breast examinations. —Dan Belson, Baltimore Sun, 1 Jan. 2024

Your portion of the cost-sharing can include deductibles, copayments, and/or coinsurance. —Elizabeth Davis, Verywell Health, 27 Feb. 2024

Medicaid also offers more robust coverage with minimal cost-sharing requirements such as copayments, coinsurance and deductibles that are common with ACA plans. —Ken Alltucker, USA TODAY, 14 Jan. 2024

Medicare bans drug company coinsurance assistance on similar reasoning. —John Wilkerson, STAT, 29 Nov. 2023

Ashley Bach, a Regence spokesperson, confirmed to KHN that both stays now will be covered as emergency, in-network services, eliminating Swedish’s coinsurance charges. —Kaiser Health News, oregonlive, 2 Mar. 2023

Previously, the practice was only allowed when drug companies give coinsurance assistance for brand drugs with generic competition. —John Wilkerson, STAT, 17 Jan. 2024

Deductibles, copayments, and coinsurance are all types of cost-sharing. —Elaine Hinzey, Verywell Health, 17 Dec. 2023

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