The Champagne toasts and wedding cake may have passed, but there still is time for claiming whose is whose. Postnuptial agreements, the figurative younger sibling of the better-known prenuptial agreements, offer legal documentation of spousal understandings, should marital circumstances change in the future. But if you’re happily married, why bring attorneys into the picture?

These agreements are not documents created to lure happy couples into divorce court. A postnup is “a written agreement between a husband and wife after the marriage has taken place where they plan for the future, in case of a dissolution of the marriage or death of a spouse,” says family law attorney Margo Green, of Green Cordonnier & House. She explains ‘postnups’ often are drafted because of changing circumstances, and gives an example of a married couple: Imagine the wife suddenly comes into a multi-million dollar inheritance and the husband, who has children from another marriage, agrees that the finances are entirely hers. However, if a divorce ever occurs, the husband does not want to be required to pay spousal support, as she has financial security; and should he die, he wants his assets to go entirely to his children, not his wife. To document this decision, a postnup could be drawn, explaining what belongs to each party—things that could not have been decided upon before the start of the marriage.

According to family law attorney Barbara Behrens, of Behrens Law Firm, these documents also can be used to lower relational stress by determining what (e.g., a business, the house) belongs to whom. “But in my experience, it has mostly been that they go into a new marriage and want to make sure their children from a first marriage get their assets.”

Separating a prenuptial and postnuptial agreement is merely the prefix and its associated meaning. “The only difference is that one was drafted and executed prior to the marriage,” says family law attorney Sam Hais, of Hais, Hais, Goldberger and Lambson, P.C. The effectiveness of the document may be another difference, although there is major discrepancy regarding their validity in court. “My experience is this: Judges who understand marital agreements and are experienced in having practiced family law understand there is no real difference between a prenuptial agreement and a postnuptial agreement,” Hais says. “They’re all marital agreements.”

On the other side, Green, who notes she does not in any way advocate for postnups, says they often do not hold up in court. “Judges don’t like them. They don’t see a reason for them.” Not even in the case of her example? According to Green, while that example couple may have a reason to want a postnup, Missouri law states that the inheritance would be untouchable if the funds were kept completely separate under the wife’s name. Furthermore, Green explains that most judges would see this example couple and realize the wife does not require post-marriage spousal support. “I don’t see the reason for them. I don’t see why people need them.”

So it seems the jury may still be out on this issue. As with any important life event that requires a legal document, it’s best to consult with an attorney you trust before taking any significant steps.

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