The below content should be reviewed in conjunction with the in-depth federal coverage of this topic provided above.
- Residents are subject to Missouri income tax withholding for work performed in the state and for work performed in another state for a Missouri employer, unless the employer withholds income tax for the state where the work was performed. Nonresidents working for a Missouri employer are subject to Missouri income tax withholding if the nonresident employee performs all services in Missouri. A different rule applies if only part of the nonresident's services were performed in Missouri. See Withholding on Residents, Nonresidents and Expatriates.
- Employers use the information from each employee's Form MO W-4 to determine the amount of income tax to withhold from their pay. Within 20 days after hiring an employee, the employer must submit a copy of the form to the Missouri Department of Revenue. See Employee's Withholding Allowance Certificate.
- The method of withholding on payments of supplemental wages, such as bonuses, depends on whether they were paid together with, or separately from, regular wages. See Supplemental Wages.
- Missouri employers must provide each employee with two copies of Form W-2, Wage and Tax Statement, by January 31 for the immediately preceding calendar year. A different rule applies to terminated employees. See Form W-2 Requirements.
- Missouri employers are required to keep certain income tax withholding records for at least three years. See Recordkeeping Requirements.
- In addition to state income tax withholding, certain employers in Missouri must withhold for local payroll taxes. See Local Payroll Taxes.