Co-insurance

Coinsurance in insurance, is the splitting or spreading of risk among multiple parties.

In the United States

In the U.S. insurance market, co-insurance is the joint assumption of risk between the insurer and the insured. In title insurance, it also means the sharing of risks between two or more title insurance companies.

In health insurance

In health insurance, coinsurance is sometimes used synonymously with copayment, but copayment is really fixed while the coinsurance is a percentage that the insurer pays after the insurance policy's deductible is exceeded up to the policy's stop loss. It is expressed as a pair of percentages with the insurer's portion stated first. The maximum percentage the insured will be responsible for is generally no more than 50%. Once the insured's out-of-pocket expenses equal the stop loss the insurer will assume responsibility for 100% of any additional costs. 70–30, 80–20, and 90–10 insurer-insured coinsurance schemes are common, with stop loss limits of $1,000 to $3,000 after which the insurer covers all expenses.