Employers in Missouri must conform with these state rules relating to income tax withholding and administration.
General Withholding Requirement: Missouri income tax generally must be withheld from wages paid to resident employees for services performed either within or without the state and from wages paid to nonresident employees for services performed in the state.
However, if a resident performs 50% or more of his or her services in another state, and that state imposes a tax on the compensation paid for those services, the resident may file an affidavit on Form MO W-4C with the employer (who must submit the original to the Department of Revenue). By filing this affidavit, the resident will be exempt from Missouri withholding.
Employee Withholding Exemption Forms: Missouri Form MO W-4 must be completed by each employee, to determine the appropriate level of state income tax to withhold from earnings. Of course, Federal Form W-4 also must be completed by each employee, to determine the appropriate level of federal income tax to withhold from earnings.
Reciprocal Agreements: None.
Administration:
Missouri DOR Taxation & Collection
Employer Withholding Tax
P.O. Box 3375
Jefferson City, MO 65105-3375
Telephone: 573-751-3505
Local Tax Jurisdictions: Kansas City (employees earnings tax); St. Louis (employer payroll expense tax and employees earnings tax).