A coinsurance penalty is a payout reduction when insured values are too low relative to the policy’s required percentage.
Why it occurs
The insured must maintain a minimum coverage level tied to property value. If coverage is below that level, the insurer pays only a proportional share on a claim.
Claims and reserve effect
Underestimated limits create a weaker loss transfer than expected. This increases disputes, increases reserve adjustment activity, and can trigger stronger underwriting review on renewal.
Underwriting logic
Adjusting required policy values and enforcement of valuation updates are key controls for limiting coinurance penalties across large books.
Scenario
Property is valued at 100,000 and a policy requires 80% coinsurance. If only 60,000 is insured and a loss occurs, the insurer applies a proportional settlement rather than full claim payment.