Mo. Rev. Stat. § 285.125
285.125 Reduced health care premiums for nonsmokers permitted.
285.125. Reduced health care premiums for nonsmokers permitted. — Notwithstanding any other provision of law to the contrary, an employer shall be permitted to provide or contract for health insurance benefits at a reduced premium rate for employees who do not smoke or use tobacco products.
(L. 2005 H.B. 596)