Coinsurance Penalty Calculator
Determine if your property insurance meets the coinsurance requirement and calculate any potential penalties on claims.
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Most policies require 80%, 90%, or 100%
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What is Coinsurance?
Coinsurance is a clause in property insurance policies that requires policyholders to insure their property to a specified percentage of its actual or replacement value. This clause exists to encourage property owners to carry adequate coverage. If a policyholder is underinsured relative to the coinsurance requirement, the insurer will proportionally reduce claim payments, effectively making the policyholder a co-insurer of their own property.
The coinsurance percentage is stated in the policy and typically ranges from 80% to 100% of the property's replacement cost value. The higher the percentage, the more coverage you must carry to avoid a penalty.
The 80% Rule
The most common coinsurance requirement is 80%. This means you must insure your property for at least 80% of its replacement cost value. For example, if your property is worth $500,000, you need at least $400,000 in coverage to avoid a coinsurance penalty.
$500K property insured for $400K+ (80%+). Full claim payment minus deductible.
$500K property insured for $300K (60%). Claim reduced proportionally.
How to Avoid Coinsurance Penalties
Get regular property appraisals
Property values change over time due to market conditions, improvements, and inflation. Regular appraisals ensure your coverage keeps pace.
Review coverage at every renewal
Use each policy renewal as an opportunity to verify that your coverage limits still meet the coinsurance requirement.
Account for improvements and renovations
Any property upgrades increase its replacement cost. Update your policy after significant renovations.
Consider an Agreed Value endorsement
This endorsement suspends the coinsurance clause for the policy period. You and the insurer agree on the property value upfront.
Work with a knowledgeable broker
An experienced commercial insurance broker can help you accurately value your property and avoid coverage gaps.
Frequently Asked Questions
What is a coinsurance clause?
A coinsurance clause is a provision in a property insurance policy that requires the policyholder to insure their property to a certain percentage of its value, typically 80%, 90%, or 100%. If the insured fails to carry enough coverage, the insurer will reduce claim payments proportionally.
How is the coinsurance penalty calculated?
The penalty is calculated by dividing the amount of insurance you carry by the amount you should carry (the required amount). That ratio is then multiplied by the covered loss (loss minus deductible). The difference between your covered loss and the reduced payment is your coinsurance penalty.
Does coinsurance apply to every claim?
Coinsurance only penalizes you if you are underinsured at the time of the claim. If you carry the required amount of insurance or more, coinsurance has no negative effect on your claims. The penalty activates only when the insurance carried is less than the coinsurance requirement.
What percentage should I insure my property for?
You should insure your property for at least the percentage specified in your coinsurance clause, which is most commonly 80% of the property’s replacement cost value. Many commercial policies require 90% or 100%. Always check your specific policy language.
Can I avoid coinsurance penalties?
Yes. Ensure your coverage limits meet or exceed the coinsurance requirement based on current replacement cost values. Review your coverage annually to account for property appreciation, renovations, or inflation. Some policies offer an Agreed Value endorsement that waives the coinsurance clause entirely.
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