DEFINITION of 'Coinsurer'
One of the parties that provides additional insurance to the same person or policy. A Coinsurer provides partial coverage along with other coinsurers. Coinsurers are generally used when the amount being covered is too large for a single insurer to cover by itself. For example, after a fire, the primary insurance company will cover the majority of the schedule, while the coinsurer will be responsible for the rest.
BREAKING DOWN 'Coinsurer'
In some instances, state or federal law may dictate that some risks must be jointly insured by several coinsurers in order to adequately diversify the risk of a possible large claim. Coinsurers will share in any claim or loss for the proportionate amount of risk that they take on.