At-will employment doctrine
Missouri follows the employment-at-will doctrine. Absent a contract for a definite term, contrary statutory provision, or public policy exception, an employer may terminate the employment relationship at any time, with or without cause. The same rule applies to employees, who may quit at any time for any reason. The doctrine imposes no notice requirement on either party.
Source: Am. Fed'n of State, Cnty. & Mun. Employees, AFL-CIO, Council 61 v. State, 653 S.W.3d 111, 122 (Mo. 2022) (en banc); Missouri Department of Labor — Wages, Hours and Dismissal Rights
Final paycheck timing — discharge vs. resignation
Missouri imposes different final-paycheck deadlines depending on whether the separation was employer-initiated or employee-initiated.
Involuntary termination (discharge)
When an employer discharges an employee or refuses to continue employment, the unpaid wages earned at the contract rate "shall be and become due and payable on the day of the discharge or refusal to longer employ." The statute applies to any person, firm, or corporation doing business in Missouri and covers discharges "with or without cause."
If the employer does not pay immediately, the employee may request in writing that the wages be sent to "any station or office where a regular agent is kept." If the money or a valid check does not reach that location within seven days of the written request, the statute triggers a penalty: wages continue to accrue at the same contract rate from the date of discharge until paid, capped at sixty days of continuing wages.
Commission-based employee exception
RSMo § 290.110 excludes employees "whose remuneration for work is based primarily on commissions and whose duties include collection of accounts, care of a stock or merchandise and similar activities and where an audit is necessary or customary in order to determine the net amount due." For this category, the immediate-payment and penalty provisions do not apply.
Voluntary resignation (quit)
Missouri law does not specify when final wages are due when an employee voluntarily quits. The Missouri Department of Labor and Industrial Relations states, "There are no requirements under Missouri law that address when wages are due when an employee quits a job." The agency notes that if wages are not paid by the next regular pay period, wages can be collected by legal action.
Source: RSMo § 290.110; Missouri Department of Labor — FAQ: Final wages when employee quits; Missouri Department of Labor — FAQ: Final wages when employee is terminated