Coinsurance is the percentage of medical expenses that you owe after you have paid your deductible. For example, if your coinsurance is 20%, you would owe that percentage of your plan’s allowed amount for a specific medical service after your deductible is paid.
If you receive $100 worth of services during a visit and you have 20% coinsurance, you would owe $20. Health insurance picks up the rest.
The amount you owe in coinsurance can’t exceed your plan’s out-of-pocket maximum in a given year.