Many insurance policies contain coinsurance clauses which require policyholders to purchase an amount of insurance that accurately reflects the value of their insured property.   If less than a certain percentage of the accurate value is purchased, policyholders may not be able to fully recover in the event of a loss..

Coinsurance clauses can be confusing and often leave policyholders in distress. The good news for policyholders is that a little education can go a long way in this area of insurance law. If you understand the basic principle that you must maintain insurance on a certain percentage of the value of your property, then you will be fully insured when disaster strikes.


Coinsurance is a property insurance provision that penalizes the insured’s loss recovery if the limit of insurance purchased by the insured is not at least equal to a specified percentage (commonly 80 percent) of the value of the insured property.. For example, if a building valued at $250,000 is insured with a policy containing an 80% coinsurance clause, the policyholder must purchase at least $200,000 in coverage. If the policyholder purchased less than $200,000, he or she would be responsible for a proportionate share of the loss.


Most commonly, yes. Some states, including Kentucky, have passed statutes voiding coinsurance clauses in property insurance policies which insure risks associated with fire or storm damage on real property. However, in states that have not passed a statute prohibiting coinsurance clauses, courts follow the common law and uphold them.


The basic formula for determining whether you have enough coverage is:

Actual Amount of Insurance divided by the Required Amount of Insurance then multiplied by the Amount of Loss. This equals the amount the insurance company will pay, less any applicable deductible.

More plainly, let’s assume we have a building valued at $100,000. Under an 80% coinsurance clause, an insured would be expected to insure 80% of these values, or $80,000.

Now, let’s consider two scenarios, the amount of the loss in each case is $30,000:

First, the policyholder only carries $50,000 in coverage:

($50,000/$80,000) x $30,000 = $18,750 (less deductible). The policyholder is forced to pay, or self-insure, the shortfall of $11,250.

Second, the policyholder carries the full $80,000 required under his policy:

($80,000/$80,000) x $30,000 = $30,000 (less deductible). In this example, the policyholder would receive full benefits.

Some policyholders choose to self-insure and rely on savings. However, most policyholders purchase insurance with the intent to be fully covered. As the examples illustrate, the unknowing policyholder can suffer great financial hardship by not purchasing the amount of insurance required by the coinsurance provision.

It is important that all policyholders know whether their policies contain a coinsurance clause and, if so, whether they have purchased the amount of insurance required to receive the full benefits they expect. Regular appraisals can ensure that property values, inflation, and depreciation are taken into account in your insurance limits. An evaluation or appraisal once every three years is a good rule of thumb, but may or may not be sufficient depending on the circumstances.