Coinsurance is the amount of money you must pay for a health service, such as a doctor's appointment or a prescription calculated as a percentage of the total cost of care. For instance, you may have a 20% coinsurance. If a doctor's visit costs $100, then you pay $20. Your health plan pays $80. You may have to pay your deductible before the coinsurance rate starts to apply.


WebMD Definition Reviewed by Sarah Goodell on July 24, 2018
© 2017 WebMD, LLC. All rights reserved.

WebMD Special Sections