Condition of average
Condition of average (also called underinsurance[1] in the U.S., or principal of average,[2] subject to average,[3] or pro rata condition of average[4] in Commonwealth countries) is the insurance term used when calculating a payout against a claim where the policy undervalues the sum insured. In the event of partial loss, the amount paid against a claim will be in the same proportion as the value of the underinsurance.
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average clause
a part of an insurance policy that states that if the insurance value of a property at the time of loss or damage is less than its real value, payment by the insurance company will be reduced according to the difference. For example, if a piece of jewellery worth £10,000 has an insurance value of £5,000, 50% of its real value, the insurance company will pay £2,500, which is 50% of the insurance value
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coinsurance provision
A property insurance provision that penalizes the insured's loss recovery if the limit of insurance purchased by the insured is not equal to or greater than a specified percentage (commonly 80 percent) of the value of the insured property. The coinsurance provision specifies that the insured will recover no more than the following: the amount of the loss multiplied by the ratio of the amount of insurance purchased (the limit of insurance) to the amount of insurance required (the value of the property on the date of loss multiplied by the coinsurance percentage), less the deductible. The amount of the loss that is not payable to the insured as a result of failure to comply with the coinsurance provision is commonly referred to as a coinsurance penalty. In commercial property insurance policies, it is sometimes possible to avoid the possibility of a coinsurance penalty with an agreed value provision.
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coinsurance clause
Insurance policy stipulation that a building must be insured for at least a certain percentage (usually 80 percent) of its insurable value (appraised or market value of the property less value of land) in order to collect the full amount of a partial-loss claim on it.

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