The legal age at which a person becomes competent to contract in Missouri is eighteen years and any rule or provision of the common law to the contrary is hereby abrogated.
Mo. Rev. Stat. § 431.055
Persons competent to contract when eighteen years of age
Effective: 07 Jan 1975, see footnote; (L. 1974 2d Ex
Official source: Missouri Revisor of Statutes. Reproduced from public-domain Missouri statutes; confirm against the official source for the current text. Not legal advice.