Which is based on a dollar amount?

A copayment is a fixed dollar amount that a policyholder pays at the time of receiving a medical service or filling a prescription. This payment is predetermined by the insurance plan and doesn't vary based on the cost of the service. For example, a health insurance policy may specify a copayment of $20 for a doctor’s visit or $10 for each prescription medication. This makes copayments distinct from other terms in health insurance, such as coinsurance or deductible, which are typically calculated as a percentage of costs or based on annual limits rather than a set dollar amount.

In contrast, coinsurance represents a percentage of costs that the insured is responsible for after meeting the deductible. A deductible is a specified amount that must be paid out of pocket before the insurance begins to cover costs. Premiums are regular payments made to the insurance provider for maintaining coverage, but they do not pertain to individual services. Therefore, the fixed nature of copayments makes them the answer that is based on a dollar amount.