Mo. Rev. Stat. § 148.090
Each bank and each trust company organized under the laws of this state and each national banking association organized under the laws of the United States to be located in Missouri, with the date of its certificate of due organization, or the equivalent thereof as a result of determination on appeal, or its certificate of authority to commence business, as the case may be (which are relevantly herein referred to as "its certificate") subsequent to July 1, 1946, shall be subject to the tax imposed by this law for the calendar year in which it receives its certificate and the first taxable year thereafter measured by its net income, as defined in section 148.040, for the portion of the calendar year unelapsed on the date borne by its certificate with the rate of tax as provided by section 148.030, and with credit against said tax for all taxes and contributions for which credit is permitted by section 148.030, which taxes or contributions are paid during the portion of the calendar year unelapsed on the date borne by its certificate. For each other taxable year each banking institution in this section referred to shall be subject to all the provisions of this law. Any tax imposed by this law due for the calendar year in which it receives its certificate shall be payable by each banking institution to which this section applies to the director on or before June first of the year following the year in which it receives its certificate, and except as to this particular the provisions of sections 148.040 to 148.070 and section 148.100 shall be applicable.
§ 148.090, RSMo