Mo. Rev. Stat. § 488.014

No court of record in this state, municipal division of the circuit court, or any entity collecting court costs on their behalf shall be required to refund any overpayment of court costs in an amount not exceeding five dollars or to collect any due court costs in an amount of less than five dollars. Any such overpaid funds may be retained by the county for the operation of the circuit court, except any overpaid funds owed to a municipal division of the circuit court may be retained by the municipality for the operation of the municipal court.