Wyo. Stat. § 26-23-103: Return of excess premium in certain cases of total destruction.

If the insured property is totally destroyed and the total amount of loss is less than the total amount insured thereon as to the hazard causing the loss, the insurer shall return to the insured at the time of payment of the loss the amount of premiums paid under the policy then in force for the excess of insurance over the fair value of the property at the time of the loss. This section does not apply to insurance of replacement value.