Beginning on January 1, 2028, a health insurance carrier (carrier) of an individual or group health benefit plan in Colorado (plan) shall, when calculating a covered person's contribution to an out-of-pocket maximum or cost-sharing requirement under the plan, account for and credit to the covered person's contribution an out-of-pocket expense that the covered person incurs by purchasing a prescription drug directly from a pharmacy or direct-to-consumer platform (contribution credit). The carrier shall apply the contribution credit to the out-of-pocket maximum or cost-sharing requirement that is applicable in the plan year in which the out-of-pocket expense was incurred. To receive a contribution credit, a covered person must provide to the carrier proof of payment for a direct purchase of a prescription drug, such as an itemized receipt or pharmacy record, within 90 days after making the purchase (proof of payment). The carrier may request additional information or documentation if the proof of payment is insufficient or incomplete. The carrier shall not apply a contribution credit in the following circumstances:For an amount of a covered person's out-of-pocket expense incurred by the direct purchase of a prescription drug that is greater than the amount the covered person would have incurred if they had obtained the same prescription drug in the same plan year from an in-network pharmacy and pursuant to the terms of their plan;If the covered person does not provide proof of payment;If the covered person incurred the out-of-pocket expense by purchasing a prescription drug that is not covered under the formulary of the covered person's plan, unless the carrier grants an exception; orIf the covered person does not comply with the carrier's utilization management processes, including prior authorization and step therapy protocols required under the covered person's plan.(Note: This summary applies to this bill as enacted.)