Co-Insurance is the percentage of a medical bill you have agreed with the insurer to undertake yourself in the event of claim.
This agreement is usually in exchange for lower premium charges from the insurer.
Example 1 - Co-insurance of 10%, Medical Bill $10,000
In this scenario, you will have to bear 10% of $10,000 -> $1,000.
The insurer will pay the remainder of $9,000.
Example 2 - Co-insurance of 10%, Deductibles of $2,000, Medical Bill $10,000
In this scenario where the insured has agreed to undertake both deductible and co-insurance liabilities, the deductibles will usually be applied first, followed by the co-insurance.
In this scenario, you will have to bear the deductibles of $2,000.
For the remainder of bill, $8,000.
The co-insurance of 10% will be applied, henceforth you will have to bear an additional amount of 10% of $8,000 -> $800.
In total, you will be bear $2,800 (Deductible $2,000 + Co-insurance $800) out of the $10,000 Medical Bill.
The insurer will pay the remainder of $7,200.