Not every couple signs a prenup before the wedding.A postnuptial agreement lets you do essentially the same thing after you’re already married. Whether you skipped a prenup the first time around, started a business together, or just want more financial clarity going forward, a postnup can put those terms in writing. This guide covers what a postnuptial agreement actually is, how it works, and the basic legal concept behind it.
This guide is part of our broader guide to family law in Tennessee, and pairs closely with our guide to prenuptial agreements, so if you’re trying to decide between the two, that’s worth a look too.
Thinking about a postnuptial agreement? Call us at (931)245-5060 and we’ll help you figure out if one makes sense for you.
A postnuptial agreement is a written contract signed by spouses after they’re already married, spelling out how they want to handle financial matters, especially property division and support, if the marriage were to end in divorce or one spouse were to pass away. It’s built on the same basic idea as a prenuptial agreement. The main difference is simply timing: a prenup is signed before the wedding, whereas a postnup is signed sometime after.
Couples often turn to a postnup after some kind of life event or turning point, starting a business, receiving an inheritance, or working through a rough patch. It’s a way of catching up on financial planning that didn’t happen before the marriage started.
There’s no waiting period and no deadline. Unlike a prenup, which has to be signed before the wedding, a postnup can be signed at any point after the marriage begins, whether that’s a few months in or decades later. The only real timing consideration is practical, not legal: since there’s no wedding date creating pressure, couples generally have the freedom to take as much time as they need to negotiate fair terms and get proper legal advice before signing.
At its core, a postnup works like any other contract between two people, just with some extra legal scrutiny given that it’s between spouses. Generally:
Both spouses negotiate the terms together, ideally each with their own attorney representing their individual interests.
The agreement covers whatever financial matters the couple wants to address, within the legal limits described below.
It has to meet certain legal formalities to actually be enforceable later.
Once signed, it becomes a binding contract, though it can be modified or revoked later if both spouses agree to change it.
It only becomes directly relevant if the marriage later ends in divorce, or when a spouse dies; until then, it mostly just sits on file as a plan for those situations.
A postnup can address many of the same financial matters as a prenup, including:
Classifying property as separate or marital, clarifying what belongs to each spouse individually versus what’s jointly owned.
How property and debt would be divided if the marriage ends in divorce.
Alimony (spousal support), including whether it would be paid, how much, or whether it’s waived.
Protection for a business, especially one started or grown during the marriage.
Protection for an inheritance or other family assets received during the marriage.
How existing or future debt will be handled between the spouses.
Coordination with estate planning, making sure the agreement lines up with wills, trusts, and beneficiary designations.
Just like a prenup, a postnup has real limits on what it can control: child custody, which has to be decided based on the child’s best interests at the time of a divorce, not locked in by an earlier agreement; child support, since parents can’t sign away a child’s right to support in advance; anything illegal, or that seems designed to encourage divorce; and purely personal or lifestyle provisions, like household responsibilities, which courts generally won’t enforce even if a couple includes them.
ennessee’s statute specifically addressing premarital agreements, Tenn. Code Ann. § 36-3-501, is written to cover agreements made in contemplation of marriage, meaning agreements signed before the wedding. Postnuptial agreements, signed after the marriage has already happened, fall into a bit of a different legal space. Tennessee courts have still recognized and enforced postnuptial agreements, generally treating them under broader contract law principles rather than that specific premarital agreement statute.
In practice, this usually means courts look for many of the same things they’d look for in a prenup: a written agreement, voluntary signatures, full financial disclosure, and terms that aren’t unconscionable, but with the understanding that spouses already have an existing marital relationship and, in some cases, closer scrutiny of whether the agreement was truly voluntary. Because this area relies more heavily on case law than a single clear statute, it’s especially important to work with an attorney who can confirm how Tennessee courts are currently treating these agreements.
The two are closely related, but a few things set them apart. Despite these differences, the practical goal is usually the same: getting clear, written financial terms in place before they’re actually needed.
A prenup is signed before the wedding, a postnup is signed sometime after.
A prenup is supported by a specific Tennessee statute; a postnup relies more on general contract law principles as applied by the courts.
Prenups are often about protecting what each person is bringing into the marriage. Postnups are often prompted by something that happened during the marriage.
Because spouses are already married, postnups can sometimes face closer examination of whether they were truly voluntary, compared to a prenup signed before that dynamic existed.
Never getting a prenup before the wedding, and wanting to put similar protections in place now.
Starting or growing a business during the marriage, and wanting to protect it going forward.
Receiving a significant inheritance, and wanting to keep it clearly separate.
Reconciling after a rough patch, sometimes including infidelity or a near-divorce.
Addressing debt issues, clarifying who’s responsible for what.
One spouse becoming a stay-at-home parent, and wanting to formally address how that affects future financial planning.
Replacing or updating an old prenup that no longer reflects the couple’s actual life or finances.
Coordinating with a new or updated estate plan.
Instead of wondering what would happen financially if the marriage ended, both spouses know exactly where they stand.
Full disclosure during the process often means both spouses actually understand the household’s full financial picture for the first time.
Whatever you’re trying to protect gets clearly defined and documented.
The process of negotiating a postnup tends to force honest conversations about money.
With major financial terms already agreed upon, a divorce is far less likely to turn into a drawn-out fight.
A postnup can be built to work hand-in-hand with your will or trust.
Couples can clearly define who’s responsible for what, rather than leaving it to be sorted out under default law later.
For a lot of couples, simply having the conversation and getting it in writing removes a background source of financial anxiety from the marriage.
Yes, and often for the same reasons a prenup might be challenged. Postnups can face an added layer of scrutiny compared to prenups, since courts sometimes look closely at whether a spouse felt they had a genuine choice, given that the marriage, and everything tied to it, is already underway by the time a postnup gets signed.
It wasn’t in writing or properly signed.
One spouse was pressured or coerced into signing.
There wasn’t full and fair financial disclosure.
The terms were unconscionable, meaning severely one-sided given the circumstances.
One spouse lacked the capacity to understand the agreement.
There was fraud involved, such as hiding assets or debts.
Postnups negotiated in the heat of a rough patch are more likely to be poorly thought through, and more vulnerable to a duress claim later.
A single attorney can’t fully represent both spouses’ separate interests.
Leaving out assets or debts, even by accident, can undermine the whole agreement later.
An agreement that clearly favors one spouse invites a stronger challenge down the road.
Terms that felt clear at signing can turn into a real dispute years later.
A postnup that only addresses divorce can end up conflicting with a will or estate plan later.
Life changes, and a postnup signed years ago may no longer reflect your actual finances or goals.
An agreement built out of guilt, anger, or fear often ends up poorly balanced compared to one negotiated calmly.
Here’s roughly what putting together a postnup looks like, step by step.
Understanding the actual goal, whether that’s protecting a business, clarifying debt, or moving forward after a rough patch, shapes what the agreement should actually cover.
Both spouses should lay out a complete, honest financial picture.
Separate representation protects both people and strengthens the agreement’s enforceability.The other person has to be formally notified of the petition and any temporary order already in place.
Work through what you both actually want addressed.
Your attorneys turn the negotiated terms into a legally sound written document.
Both spouses should have a genuine chance to review and ask questions before signing.
Unlike a prenup, there’s no wedding date forcing the timeline, so take the time to get it right.
Make sure both spouses know where to find it.
Postnuptial agreements often connect to other family law topics.
A postnup is only as strong as how carefully it was put together. At Dahl Family Law, we bring:
A clear understanding of how Tennessee courts currently treat postnuptial agreements.
Careful attention to full financial disclosure and fair terms, so the agreement holds up if it’s ever needed.
A thoughtful, low-pressure process, especially important for couples negotiating this after a difficult period.
Coordination with your broader estate plan, so everything works together.
Not necessarily. While some couples do turn to postnups after a rough patch, plenty of others sign one simply because their financial situation changed, a new business, an inheritance, or just a desire for more clarity, without anything being "wrong" in the marriage.
Yes, as long as there is other consideration. There's no requirement that a couple be struggling to sign a postnuptial agreement.
Yes, a postnup can update, replace, or supplement an existing prenuptial agreement if a couple's circumstances or goals have changed since they got married.
It's not strictly required, but it's strongly recommended. Separate representation helps demonstrate the agreement was genuinely voluntary and fair, which matters a lot if it's ever challenged later.
Whether you’re catching up on planning you missed before the wedding or addressing something new that’s come up during your marriage, a well-drafted postnup can bring real clarity to your financial future together.
Dahl Family Law provides representation in a wide range of family law matters, including:
This guide is intended for general informational purposes only and does not constitute legal advice. Postnuptial agreements are fact-specific, and enforceability depends on the details of your situation. Please consult with a licensed Tennessee family law attorney regarding your specific circumstances.
