How do I figure out my coinsurance?


Editorial team Published on

You can calculate your payment using the A Simple Guide to Calculate Your Coinsurance Payment for healthcare, or use the Claimspages Coinsurance Calculator for property and casualty claims.

Coinsurance calculations differ depending on whether you are looking at health insurance or property insurance.

Health Insurance Coinsurance

In health insurance, coinsurance is your share of the costs of a covered service, calculated as a percent of the allowed amount. It applies after you meet your annual deductible.

  • Formula: Network-Approved Amount × Coinsurance Percentage = Amount You Owe
  • Example: If the approved amount for a medical procedure is $1,000 and your coinsurance is 20%, you multiply $1,000 by 0.20 to get $200. Your insurance pays the remaining 80% ($800), assuming your deductible has already been met.

Property and Casualty Insurance

In property insurance (like homeowners or commercial building insurance), coinsurance is a clause requiring you to insure your property to a specific percentage (usually 80%) of its replacement value. If you underinsure, a penalty reduces your claim payout.

  • Formula: (Amount Carried ÷ Amount Required) × Loss Amount − Deductible = Claim Payout
  • Amount Required: Property Replacement Value × Coinsurance Percentage (typically 80%)
  • Example: If your building is worth $100,000 and has an 80% requirement, you must carry at least $80,000 of insurance. If you only carry $50,000 and suffer a $10,000 fire loss with a $500 deductible, your payout is ($50,000 ÷ $80,000) × $10,000 − $500 = $6,250 − $500 = $5,750.