What is the difference between a co-payment and co-insurance? a. Co-payment refers to two spouses paying for the same coverage, and co-insurance refers to two spouses receiving the same benefits. b. Aco-payment is a flat fee for each service, and co-insurance is based on a percentage of the costs incurred. c. Co-payment is when a group of individuals work to cover each other's medical expenses, and co-insurance is when an individual has multiple insurance policies from different companies. d. A co-payment is when an employer helps an employee pay for insurance premiums, and co- insurance is when an employer helps an employee find better insurance than they could alone.