What Is Coinsurance?

Your share of a health service covered by your insurance.

Coinsurance is your share of a health service, such as an x-ray, that is covered by your insurance plan. Like a copayment, coinsurance is another form of cost sharing, when you share the cost of your healthcare with your insurance company.

Coinsurance fees kick in after you have met your deductible. This out-of-pocket payment is a percentage of the total amount your insurance plan has decided the health service should cost, also called the “allowed amount.” Allowed amounts are pre-determined in a contract between your health insurance company and your healthcare provider.

Let’s say a health plan’s allowed amount for a visit to your doctor is $100, you have already met your deductible, and your coinsurance payment is 20 percent of the cost of that visit. Your cost, or coinsurance, for the visit would be $20.

Different insurance plans have different coinsurance fees for certain services. It is very important to understand all of your out-of-pocket costs before you sign up for a health insurance plan. You should always consider all of your anticipated healthcare costs, as well as plan for unanticipated healthcare costs, before choosing a health insurance plan.