What is the definition of coinsurance?

Coinsurance is defined as a percentage of the cost of services that a policyholder is required to pay after meeting their deductible. This means that once the deductible has been paid, the insured person is responsible for a specific percentage of costs for medical services received, while the insurance company covers the remaining percentage. For example, if a health insurance plan has a coinsurance rate of 20%, the policyholder would pay 20% of the costs for treatments or services, and the insurer would cover the remaining 80%.

This mechanism differs from a fixed amount paid for services, which would be a copayment, and does not encompass the total amount owed for care, which includes all out-of-pocket expenses such as deductible, copayments, and coinsurance. It's also not a definition that covers all costs being paid by insurance, as coinsurance specifically pertains to shared costs between the insurer and the insured.