Missouri: B
Statutes
Missouri has not passed the UPAA, but allows marriage contracts in writing from laws enacted in 1939!
RSMo § 451.220
Separate Property
All assets can remain separate property, avoiding costly divorce settlements. Joint assets and debts titled in both names are split 50/50 as marital property.
Unconscionability Single Review
Missouri reviews prenuptial agreements for unconscionability only at execution, never at enforcement. That means changed circumstances during marriage alone will not invalidate a prenup.
Unconscionability Standard
A prenup is unenforceable if the party proves: (1) failure to enter freely, fairly, knowingly, understandingly, with good faith and full disclosure; OR (2) unconscionability. Missouri defines unconscionable as inequality so extreme it "must produce exclamation." Courts invalidate only if shockingly unfair at execution.
Spousal Support Review at Enforcement
Maintenance waivers are reviewed for unconscionability only at execution, never at enforcement. A maintenance waiver that was fair at signing remains enforceable even if circumstances change dramatically, including unemployment or disability of the waiving spouse.
Timing
No minimum specified, but we recommend signing the prenup 60+ days before the wedding, with both parties having 2-3 weeks to review the final version to minimize challenge risk. Reach out to an attorney at least 4-6 months before the wedding with your draft prenup. Better yet, sign the prenup before proposing.
Independent Counsel
Not required, but separate counsel dramatically strengthens enforceability if the agreement is later challenged. Both parties must at least have the opportunity to retain counsel and a written waiver.
Financial Disclosure
Full disclosure of "the nature and extent" of all property interests required. Disclosure must be sufficient for informed decisions. Assets cannot be hidden without risking split or invalidation of the prenup. Disclose all assets $1,000+.
High Burden to Challenge
Challenging party must prove the prenup is invalid by preponderance of evidence (standard burden, not the higher "clear and convincing" requirement). Courts favor prenuptial agreements and find most properly executed agreements enforceable. Unconscionability is only reviewed at execution (signing), not enforcement (divorce), meaning courts look to uphold the agreements, not reject or modify them.
Child Support and Custody
Child support and custody clauses are unenforceable and could undermine the entire agreement. Do not include.
Case Law
McMullin v. McMullin, 926 S.W.2d 108 (Mo. App. 1996)
Court found antenuptial agreement unconscionable where it excluded wife's right to marital property and wife was unable to consult an attorney before signing, establishing the standard that inequality must be "so strong, gross, and manifest that it must be impossible to state it to one with common sense without producing an exclamation at the inequality of it."
Gould v. Rafaeli, 822 S.W.2d 494 (Mo. App. E.D. 1991)
Court upheld antenuptial agreement denying husband maintenance, attorney fees, and certain property despite financial disparity and husband's economic dependence on wife, finding that financial disparity alone does not make a prenuptial agreement unconscionable.
Miles v. Werle, 977 S.W.2d 297 (Mo. App. 1998)
Court reaffirmed the Ferry standard that prenuptial and postnuptial agreements must be entered into freely, fairly, knowingly, understandingly, and in good faith with full disclosure.
In re Marriage of Thomas, 199 S.W.3d 847 (Mo. App. S. Dist. 2006)
Listed on 2006 index Court enforced prenup eliminating wife's right to alimony and attorney's fees where wife had her own attorney, received full disclosure, parties had equal bargaining power, despite only having two days to review the agreement.
Short v. Short, 356 S.W.3d 235 (Mo. App. 2011)
Court upheld prenup signed the day before wedding where husband had equal bargaining power, claimed IQ of 160, could have afforded an attorney, and entered agreement freely and understandingly despite not having counsel.
Ferry v. Ferry, 586 S.W.2d 782 (Mo. App. 1979)
Foundational case establishing that prenuptial agreements will not be enforced unless entered into freely, fairly, knowingly, understandingly, and in good faith with full disclosure.