Mo. Rev. Stat. § 138.180

Any person may appeal in writing to the board of equalization from the assessment of his property, which appeal shall specify the matter of which he complains and which shall be filed at the office of the assessor of the city on or before the second Monday in July of each year, and any person so appealing shall have the right of appeal from decisions of the local board to the state tax commission as provided by law. There shall be no presumption that the assessor's valuation is correct.