Mo. Rev. Stat. § 285.010: List to be furnished municipalities levying an earnings tax — request, how made — contents of list — exception.

All employers within the state shall, upon request as hereinafter provided, submit to any municipal corporation levying an earnings tax a complete listing of all their employees who reside within the territorial limits or boundaries of the requesting authority and their current addresses according to the records of the employer. Any request made under provision of the law shall be made in writing and shall be mailed to the principal office of the employer. If the employer is a corporation, the written request shall be made to the registered agent of the corporation at its registered office. All written requests provided for in this section shall be by registered or certified mail. Such request may not be made more than once each year. Provided, however, sections 285.010 to 285.020 shall not apply to employers who deduct from the earnings of their employees the amount of any municipal earnings levied upon the income of the particular employee, and pay same to the municipality levying said tax.