Is a Postnuptial Agreement Enforceable in Missouri?
Yes. Missouri courts have enforced them, and the leading Missouri decision rejected the argument that a postnuptial agreement violates public policy, in those words.
That is not what most national writing on the subject suggests, and it is the answer most people are actually looking for.
A postnuptial agreement is a contract between two people who are already married and who intend to stay married. It sits alongside the rest of a Missouri dissolution framework set out in the Missouri Courts dissolution information pages. It can address how property, debt and spousal support would be handled if the marriage later ended. What follows is the standard a Missouri court applies to one, how much authority sits behind that answer, and where the law runs out.
What Did Lipic Actually Hold?
That postnuptial agreements are not against public policy in Missouri, and that the same standard used for a prenuptial agreement applies to one.
The case is Lipic v. Lipic, 103 S.W.3d 144 (Mo. App. E.D. 2003), decided on January 28, 2003.
The wife argued that an agreement signed during a marriage should be treated differently from one signed before a wedding, and that an agreement made in an effort to keep a marriage together should be void as a matter of public policy.
The Eastern District answered directly. “Had this Court believed that post-nuptial agreements were against public policy in Missouri, it could have said so in Reisenleiter. It did not, and neither will we. We do not believe that post-nuptial agreements are against public policy in Missouri.”
That sentence is the foundation for everything else on this page. A Missouri court can enforce a postnuptial agreement. It will still look hard at how the agreement was made and at whether its terms are too one sided to enforce.
Why Did the Court Compare It to a Prenup?
Because the wife’s argument rested on pressure, and the court did not accept that pressure is unique to one setting.
The opinion continues. “We can think of no public policy reasons why agreements made in contemplation of continuing a marriage should not be equally enforced. The pressures involved when one party to an ante-nuptial agreement wants to get married are at least similar to the pressures involved when one party wants the marriage to continue.”
Read what that does and does not say. It does not say pressure is irrelevant. It says the presence of pressure does not by itself decide the question. What decides it is whether the agreement was entered into freely and knowingly, whether there was disclosure, and whether the terms are unconscionable.
How Much Authority Sits Behind That?
Less than most articles imply, and knowing the limits is part of using the answer properly.
- Lipic is a Court of Appeals decision. It is the leading Missouri appellate authority on this exact question, and it is not a decision of the Supreme Court of Missouri
- It came from the Eastern District, which covers St. Louis City and St. Louis County. That makes it especially relevant here, and it remains one district’s decision
- Transfer to the Supreme Court of Missouri was denied, on the reporting available to us, which left the appellate opinion standing. A denial of transfer does not convert a Court of Appeals decision into a Supreme Court one
- Missouri has no statute written for a postnuptial agreement made during an intact marriage. Section 452.325 RSMo governs separation agreements made in connection with separation or dissolution, which is a related but different document
So the accurate sentence is narrow. Missouri courts have held that a postnuptial agreement is not against public policy. Missouri does not have a statute dedicated to them. That distinction matters when one is being drafted, and it matters more when one is being challenged.
What Standard Does a Missouri Court Apply?
The antenuptial standard, which asks two questions rather than one.
The agreement must be entered into freely, fairly, knowingly, understandingly and in good faith with full disclosure. Lipic applied that standard to a postnuptial agreement.
- How was it made. The court can look at the financial disclosure, the timing, the opportunity to read it, and whether each spouse had a genuine chance to get independent advice
- What does it say. The court can look at whether the terms are so one sided as to be unconscionable
That second question has a specific Missouri formulation, and it is routinely misquoted. In Darr v. Darr, 950 S.W.2d 867 (Mo. App. E.D. 1997), quoting McMullin v. McMullin, 926 S.W.2d 108 (Mo. App. 1996), the standard is that the 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.”
Note two words. Manifest, not clear. And an exclamation at the inequality of it, not at the unfairness. You will see both misquoted, and the mistake softens a standard that is deliberately severe.
That is a high bar. The question is not whether a postnuptial agreement was generous. It is whether the terms and the circumstances together make enforcement impossible to defend.
Does Signing Against My Lawyer’s Advice Void It?
No, and Missouri case law runs firmly the other way.
In Lipic the wife “consulted with not one, but two attorneys, both of whom advised her not to sign the agreement.” She signed it. The agreement was enforced.
Darr goes further on the same point. There the wife consulted three attorneys, all of whom advised against signing, and the agreement’s overall validity was affirmed.
The reason is not that advice does not matter. It is that independent advice tends to prove the opposite of what the challenger wants it to prove. It shows the person understood the document and the rights being given up. Choosing not to follow good advice is a different thing from being deceived or denied the chance to understand.
Which is why advice is most valuable before signature rather than after. Counsel who can change the terms is worth considerably more than counsel who can later testify that a warning was given.
What Makes a Postnuptial Agreement Fail?
Problems in combination rather than any single fact.
- Missing financial disclosure. One spouse did not know what the other owned, owed or earned
- No meaningful opportunity to understand it. Presented with little time to read, ask questions or take advice
- Terms leaving one spouse with effectively nothing. In Darr’s discussion of McMullin, the exclusion of marital property was considered together with an inability to consult a lawyer
- Ambiguous drafting. Ambiguity is not itself a ground to invalidate an agreement. It reliably produces a dispute, because two people read the same clause differently
Penrod v. Penrod, docket ED109069, decided 18 May 2021, ran the other way on similar themes. The wife reviewed the agreement with her own attorney and signed it the same evening. The Eastern District affirmed, finding neither procedural nor substantive unconscionability, in part because there had been full disclosure, adequate time with independent counsel, and the agreement did not strip her of all spousal rights. We cite Penrod by docket and date because no reporter citation for it is retrievable from a free source.
Read those two together and the pattern is clear. Disclosure, time, independent advice and terms that leave something on the table are what carry an agreement. No one of them is decisive alone.
What Has Missouri Not Settled?
Four things, and naming them is more useful than pretending this area is closed.
- Whether the Supreme Court of Missouri agrees with Lipic. The public policy holding is the Eastern District’s. The Supreme Court of Missouri has not squarely addressed it
- Whether a reconciliation agreement is treated differently. Missouri has no separately reported category for an agreement whose main purpose is preserving the marriage
- Who carries the burden on every kind of challenge. That can depend on the claim being made, and we would not describe it as settled across the board
- How far a waiver reaches. Darr held that the enforceability of the agreement’s attorney’s fees waiver had to be assessed on the financial circumstances existing at dissolution rather than at signing, and reversed and remanded on that point. A waiver of spousal maintenance under Section 452.335 RSMo raises its own questions again
That last one is frequently misdescribed as a maintenance waiver holding. It is not. Darr’s operative holding on the waiver concerns the attorney’s fees clause, and the difference matters if somebody is relying on it.
None of this argues against a postnuptial agreement. It argues for drafting one carefully, disclosing completely, and getting advice before signing rather than after.
What Does Enforceable Not Mean?
It does not mean automatic, and it does not mean unreviewable.
A Missouri court can examine both the document and the circumstances of its execution. Enforceable describes an outcome that is available, not one that is assumed.
A postnuptial agreement also cannot decide the children’s issues. Section 452.325.2 RSMo makes separation agreement terms binding on the court “except terms providing for the custody, support, and visitation of children,” and those come out of the binding provision entirely.
And it does not make the property division reopenable. Section 452.330.5 RSMo provides that the court’s order as it affects distribution of marital property “shall be a final order not subject to modification.”
It may also not answer every classification question. Under Section 452.330 RSMo, property acquired during the marriage is presumed marital unless an exception applies, and one of those exceptions is “property excluded by valid written agreement of the parties.” An agreement can say a business is separate. A later dispute can still be about the growth in that business, about marital contributions to it, or about whether the agreement addressed the question clearly enough. Our pages on marital versus separate property, dividing marital property and divorce for business owners cover those.
Who Can Help With a Postnuptial Agreement in Missouri?
Whether a postnuptial agreement holds up depends far more on how it was made than on how it was worded, and almost all of that work happens before anybody signs.
A postnuptial agreement is also modifiable in a way a judgment is not, since Section 452.370.1 RSMo governs later changes to maintenance while property stays fixed. Bardol Law Firm practices only family law and drafts and reviews marital agreements for families in St. Louis County, St. Louis City, St. Charles County and Jefferson County. You can read more about prenuptial and postnuptial agreements, about property and asset division, and our high net worth divorce practice.
Every client here has a named paralegal on the file, and we generally return calls within one business day.
Family Law, Simplified.
If somebody has handed you an agreement to sign, or you are thinking about proposing one, that is a conversation to have first rather than afterward. Contact Bardol Law Firm or call 314.918.0100.
This page is general information about Missouri law and is not legal advice. Every case turns on its own facts. The choice of a lawyer is an important decision and should not be based solely upon advertisements.