If a person makes a payment in excess of the assessed amount, the commission may issue a refund to the person for the excess amount or credit the excess amount toward the person's next assessment. For overpayments of less than $50, absent exigent circumstances, the commission will not issue a refund and will hold the excess amount as a credit toward the person's next assessment through the fiscal year in which the overpayment occurred. If a credit remains at the end of the fiscal year in which the overpayment occurred, the commission will issue a refund for any excess amount remaining.
Iowa Admin. Code r. 199-17.10