Coinsurance and copay are both terms used in health insurance plans to describe out-of-pocket expenses that policyholders must pay. However, they are not interchangeable and apply in different situations. Here are the key differences between coinsurance and copay:

Copay

• A fixed cost that an insurance policyholder pays for a specific service covered by their insurance.
• The amount of copay is predetermined and does not change, regardless of the cost of the service.
• Copays apply both before and after the deductible is met.
• Copays do not count towards the deductible but may count towards the maximum out-of-pocket limit for the year.

Coinsurance

• Paid as a percentage of the cost of a service.
• The percentage of coinsurance varies depending on the policy chosen.
• Coinsurance only applies after the deductible is met[[3]](https://www.cigna.com/knowl...