Plenty of couples never get around to a prenuptial agreement. Sometimes the subject felt awkward during the engagement. Sometimes neither spouse had significant assets at the time of the wedding. Sometimes the idea simply never came up. Years later, circumstances change. A business takes off, an inheritance arrives, one spouse leaves a career to raise children, or the marriage goes through a difficult period and the couple wants clarity going forward.
Florida law offers a solution for spouses who are already married: the postnuptial agreement. A postnup can address many of the same issues as a prenup, including property division, alimony, debts, and inheritance rights. It is signed during the marriage rather than before it, and that timing brings its own legal rules, risks, and opportunities.
This article explains what a postnuptial agreement is, why couples sign them, what they can and cannot cover under Florida law, how courts evaluate them, and what steps make a postnup far more likely to be enforced if it is ever tested in a Hillsborough County courtroom.
What Is a Postnuptial Agreement?
A postnuptial agreement is a written contract between spouses, signed after the wedding, that sets out how certain financial matters will be handled if the marriage ends through divorce or death. It can also govern how the couple manages property and finances during the marriage.
In substance, a postnup and a prenup often look very similar. Both can classify property as marital or separate, set terms for alimony, allocate debts, and waive rights in the other spouse’s estate. The difference lies in when they are signed and, as a result, which legal standards apply.
Florida’s Uniform Premarital Agreement Act, found in section 61.079 of the Florida Statutes, governs agreements signed before marriage. It does not apply to agreements signed during the marriage. Postnuptial agreements are instead evaluated primarily under Florida case law, most notably the Florida Supreme Court’s decision in Casto v. Casto, along with specific statutory rules in the Probate Code for waivers of estate rights. Those differences are important, and they are one reason working with a Florida prenup attorney who also handles postnuptial agreements makes a real difference.
A postnuptial agreement is also distinct from a marital settlement agreement. A marital settlement agreement is negotiated when a couple is divorcing and resolves the terms of that specific divorce. A postnup is signed by spouses who intend to stay married and want to plan ahead.
Why Do Married Couples Sign Postnuptial Agreements?
The reasons vary widely, but several situations come up again and again.
Starting or growing a business. When one spouse launches or expands a business during the marriage, the growth in value may be treated as marital property. Business partners and investors sometimes want assurance that a divorce will not disrupt ownership. A postnup can define how the business will be treated, protecting both the company and the couple’s working relationship.
Receiving an inheritance or gift. Under Florida law, inheritances and gifts from third parties are generally nonmarital property. That protection can be lost if the funds are commingled with marital assets, deposited into joint accounts, or used to pay down a jointly owned mortgage. A postnup can clarify the intended treatment and reduce disputes over tracing later on.
One spouse leaving the workforce. When a spouse steps away from a career to care for children or support the other spouse’s career, that decision carries long-term financial consequences. A postnup can provide that spouse with specific protections, such as a guaranteed payment or a defined share of certain assets, in exchange for clarity on other issues.
Reconciliation after marital difficulties. Some couples sign postnups after a separation, an affair, or a period of serious conflict. The agreement may be part of a decision to recommit to the marriage while giving one or both spouses a sense of security.
Fixing or replacing a flawed prenup. A prenup may have been signed without adequate disclosure, without proper witnessing for estate waivers, or on terms that no longer make sense. A postnup can update or replace it.
Estate planning and blended families. Spouses with children from prior relationships often want to ensure those children inherit specific assets. A postnup can waive elective share and homestead rights, allowing each spouse to plan their estate with more certainty.
Significant changes in income or debt. A spouse taking on substantial debt, such as business loans or student loans for an advanced degree, may want clear terms on who bears responsibility for that debt if the marriage ends.
Relocation to Florida. Couples moving to Florida from another state may want to clarify how property acquired elsewhere will be treated under Florida’s equitable distribution framework.
What Can a Florida Postnuptial Agreement Cover?
A well-drafted postnup can address a broad range of financial matters. Common provisions include:
- Classification of property. The agreement can designate specific assets as separate property, marital property, or a combination of both, including how appreciation, income, and contributions will be treated.
- Division of property on divorce. Rather than leaving division to the court under Florida’s equitable distribution statute, the couple can agree in advance how assets will be divided.
- Alimony. The agreement can set, limit, or waive spousal support, subject to certain limits discussed below.
- Debt allocation. Spouses can agree on who is responsible for particular debts.
- Business interests. The agreement can define ownership, valuation methods, and buyout terms for a business.
- Estate rights. Spouses can waive or limit the elective share, homestead rights, intestate share, and other rights in each other’s estates.
- Life insurance. One spouse can agree to maintain life insurance for the benefit of the other.
- Retirement accounts. The agreement can address how retirement assets will be treated and, because both parties are already married, can be paired with the plan-required spousal consent forms.
- Management of finances during the marriage. Some couples include terms about joint accounts, household expenses, or how particular assets will be titled.
This flexibility makes the postnuptial agreement a useful tool for couples in many different situations. The key is making sure each provision is enforceable and drafted with enough precision to prevent later disputes.
What a Postnup Cannot Do in Florida
Certain matters are off limits in any marital agreement, whether signed before or after the wedding.
Child support. Parents cannot waive or limit their children’s right to support. Child support is calculated under Florida’s guidelines at the time of divorce, and a court will not be bound by an agreement that shortchanges a child.
Time-sharing and parental responsibility. Decisions about where children will live and how parental responsibility will be shared are based on the best interests of the child at the time of the case. A postnup may express the parents’ intentions, but the court is not bound by them.
Temporary support while a divorce is pending. Florida courts have long treated a spouse’s obligation to support the other during the marriage, including while a divorce case is underway, as something that cannot be waived in advance. Provisions waiving temporary alimony and temporary attorney’s fees have historically been held unenforceable, even though agreements addressing support after the final judgment can be enforced.
Illegal or public policy violations. Terms that require illegal conduct or violate public policy will not be enforced.
Conduct-based penalties. Some couples want provisions that impose financial consequences for specific behavior, such as an affair. Florida is a no-fault divorce state, and provisions of this kind raise enforceability questions. Courts generally avoid regulating personal conduct within a marriage. If a couple wants to address this type of issue, the provision should be drafted carefully with an understanding that it may not be enforced as written, and with a severability clause so the rest of the agreement survives if it is struck.
How Do Florida Courts Decide Whether a Postnup Is Valid?
Because section 61.079 does not govern agreements signed during marriage, Florida courts apply the framework established in Casto v. Casto. Under that framework, a spouse may challenge a marital agreement on either of two grounds.
The first ground: fraud, duress, coercion, misrepresentation, or overreaching. A spouse can set aside an agreement by showing it was obtained through one of these improper means. The analysis is similar to how courts evaluate prenups. Evidence about how the agreement was presented, negotiated, and signed is central.
The second ground: an unfair or unreasonable agreement combined with inadequate disclosure. If the challenging spouse shows the agreement is unfair or unreasonable given the circumstances of the parties, a presumption arises that the other spouse concealed information or that the challenging spouse lacked adequate knowledge. The burden then shifts to the spouse defending the agreement to show either that there was full, frank disclosure before the agreement was signed, or that the challenging spouse had a general and approximate knowledge of the other spouse’s property and income.
In evaluating whether an agreement is unfair or unreasonable, courts look at factors such as the relative situation of the parties, their respective ages, health, education, and financial status, and what each party gave up and received. An agreement can favor one spouse and still be enforced. The concern is with agreements that are disproportionate to the point of unfairness when the disadvantaged spouse did not know what they were giving up.
This second ground is a meaningful difference from the premarital agreement statute. Under section 61.079, a prenup challenger generally must prove the agreement was unconscionable and also establish several disclosure deficiencies. The postnuptial framework can be more favorable to a challenging spouse, because showing unfairness shifts the burden to the other side. That makes full financial disclosure especially important in a postnup.
Why Spouses Owe Each Other More When Signing a Postnup
Before marriage, two people negotiating a prenup are, at least in legal terms, dealing with each other at arm’s length. Either can walk away. After the wedding, the relationship is different. Spouses stand in a confidential relationship and are expected to deal with each other with a high degree of candor and good faith.
That shift affects how courts view postnuptial agreements. A spouse who controls the family finances, holds information the other spouse does not, and presents an agreement for signature has a heightened responsibility to make sure the other spouse understands what is being signed. Courts are alert to situations where one spouse uses the trust inherent in marriage to obtain terms the other spouse would not have accepted with full information.
This is why the practical safeguards discussed later in this article, especially independent counsel and full disclosure, carry even more weight for postnups than for prenups.
Is Consideration Required for a Postnuptial Agreement?
With a prenup, the marriage itself serves as the bargained-for exchange. With a postnup, the couple is already married, so the question arises whether each spouse must receive something in return for the rights they give up.
In practice, Florida postnuptial agreements are usually supported by mutual promises. Each spouse typically waives certain rights in the other’s property, alimony, or estate, and those reciprocal waivers generally supply the necessary consideration. Agreements may also involve a specific transfer, such as one spouse retitling property into joint names, funding an account for the other spouse, or purchasing a life insurance policy.
Problems tend to arise when an agreement is entirely one-directional. If one spouse gives up nearly all rights and receives little or nothing in exchange, the agreement becomes more vulnerable under the unfair or unreasonable analysis described above. A balanced agreement, where each spouse gains something meaningful, is far easier to defend.
Postnups, Alimony, and Florida’s 2023 Reform
Alimony is one of the most common subjects of postnuptial agreements, and it is an area where the law has shifted recently. Florida’s 2023 alimony reform eliminated permanent alimony for cases filed after the law took effect and imposed new limits on durational alimony tied to the length of the marriage. The reform also created a presumption regarding the maximum amount of alimony that may be awarded in many cases.
For couples considering an alimony prenup in Tampa or a postnup addressing support, this reform changes the starting point. A spouse deciding whether to waive or limit alimony should understand what they would likely receive under current law without an agreement. In some situations, the reform narrows the gap between what an agreement provides and what a court would award. In others, particularly in long marriages where one spouse depends heavily on the other’s income, alimony remains a significant issue.
A Florida alimony attorney can help structure support terms that are realistic and defensible. Common approaches include:
- A lump sum payment in place of ongoing alimony
- Alimony limited to a set number of years or a specific monthly amount
- Support that increases with the length of the marriage
- A waiver of alimony balanced by a larger share of marital property or a funded account for the lower-earning spouse
Tailored terms tend to hold up better than blanket waivers, especially where one spouse left the workforce or has significantly lower earning capacity. Because a postnup can be challenged as unfair or unreasonable, a thoughtful support provision is one of the best ways to protect the entire agreement.
Postnups and Estate Rights: Additional Requirements
Postnuptial agreements often include waivers of inheritance rights, particularly in second marriages and blended families. Florida’s Probate Code, in section 732.702, allows a spouse to waive the elective share, homestead rights, intestate share, pretermitted share, exempt property, family allowance, and the preference to serve as personal representative.
Two requirements are especially important for postnups:
Fair disclosure is mandatory. For a waiver signed before marriage, the Probate Code does not require disclosure. For a waiver signed after marriage, it does. Each spouse must make fair disclosure of their estate to the other. A postnup estate waiver signed without that disclosure is vulnerable.
Two subscribing witnesses are required. The waiving spouse must sign in the presence of two subscribing witnesses. A postnup that is notarized but not properly witnessed may fail to waive estate rights, even if it is otherwise valid.
Because spouses are already married, a postnup also offers an advantage over a prenup when it comes to employer-sponsored retirement plans. Federal law generally requires a spouse’s written consent to waive survivor benefits in many 401(k) and pension plans, and a fiancé cannot give that consent before the wedding. A married spouse can. A postnup can be signed together with the plan’s spousal consent forms, which avoids one of the most common gaps in premarital planning.
The postnup should also be coordinated with wills, trusts, beneficiary designations, and deeds. An agreement that says one thing while an estate plan says another invites litigation among surviving family members.
How to Make a Postnuptial Agreement Hold Up
The same practices that protect prenups apply to postnups, and several of them matter even more because of the confidential relationship between spouses and the burden-shifting framework of Florida case law.
Provide complete financial disclosure. This is the single most important step. Each spouse should disclose assets, liabilities, and income in writing, ideally with supporting documents such as tax returns, account statements, and business valuations where relevant. Disclosure schedules should be attached to the agreement. Given how a presumption of concealment can arise if the agreement is later viewed as unfair, thorough disclosure is the strongest defense available.
Make sure each spouse has independent counsel. One attorney cannot represent both spouses in negotiating a postnup, because their interests are adverse. Each spouse should have their own lawyer who reviews the agreement, explains the rights being waived, and advises on whether the terms are reasonable. Independent counsel is powerful evidence that the agreement was entered knowingly and voluntarily.
Allow enough time. Pressure to sign quickly undermines any agreement. Spouses should have time to review drafts, ask questions, and negotiate changes. Evidence of back-and-forth negotiation helps show the agreement was not imposed.
Keep the terms balanced. A postnup that gives each spouse meaningful benefits is far more durable than one that strips one spouse of everything. Balanced terms reduce the chance that a court finds the agreement unfair or unreasonable.
Avoid signing during a crisis if possible. Agreements signed in the middle of a marital crisis, such as immediately after discovering an affair or under threat of divorce, can draw close scrutiny for duress or coercion. When a postnup is part of a reconciliation, allowing time and involving counsel becomes especially important.
Execute with full formalities. Have each spouse sign in the presence of two subscribing witnesses and a notary. This satisfies the Probate Code requirements for estate waivers and creates a strong record of execution.
Follow through. Retitle assets, update beneficiary designations, sign retirement plan consents, and revise estate planning documents so everything matches the agreement.
Review periodically. Circumstances continue to change. A postnup can be amended through a new written agreement signed with the same care as the original.
What Happens If a Postnup Is Challenged in Divorce?
When a spouse challenges a postnup, the dispute is typically raised early in the divorce case because the agreement’s validity affects nearly every other issue. The court may hold an evidentiary hearing to decide whether the agreement is enforceable before addressing equitable distribution, alimony, or attorney’s fees.
The challenging spouse may argue fraud, duress, coercion, misrepresentation, or overreaching. Alternatively, they may argue that the agreement is unfair or unreasonable, triggering the presumption that shifts the burden to the other spouse to prove adequate disclosure or knowledge. Evidence often includes the disclosure schedules, drafts and correspondence, testimony from the attorneys and witnesses, and financial records from the time of signing.
Many postnups include prevailing-party attorney’s fee provisions, and Florida courts have generally enforced those provisions in litigation over the agreement. That increases the financial stakes for both sides and encourages careful evaluation before a challenge is filed.
If a court finds part of the agreement unenforceable, such as a waiver of temporary support, a severability clause may allow the rest of the agreement to stand. Whether the court severs the provision or throws out the entire agreement depends on the wording and on how central the invalid term was to the overall bargain.
Is a Postnup Right for Your Marriage?
A postnup is not the right choice for every couple, and raising the subject requires sensitivity. For many spouses, though, a postnuptial agreement provides clarity and reduces anxiety about the future. It can protect a business, preserve an inheritance, support a spouse who has made career sacrifices, and ensure children from a prior relationship are provided for.
The conversation often goes better when framed around shared goals rather than fear of divorce. Many couples find that the process of disclosing finances and discussing expectations improves their communication. With independent counsel on both sides, the negotiation can focus on building terms that both spouses consider fair.
A Tampa prenup lawyer who regularly prepares marital agreements can explain how Florida law would treat your situation without an agreement, identify the provisions most worth including, and help draft terms that stand up to scrutiny. For couples with estate planning concerns, coordination with an estate planning attorney is often part of the process.
Frequently Asked Questions About Florida Postnuptial Agreements
Are postnuptial agreements legal in Florida? Yes. Florida courts recognize and enforce postnuptial agreements that are entered into fairly and with adequate disclosure. They are evaluated under Florida case law rather than the premarital agreement statute, and estate waivers within them must also satisfy the Probate Code.
What is the difference between a prenup and a postnup in Florida? A prenup is signed before marriage and is governed by section 61.079 of the Florida Statutes. A postnup is signed during marriage and is evaluated under case law, including a standard that allows a challenge if the agreement is unfair or unreasonable. Postnups also require fair disclosure for estate waivers, while premarital estate waivers do not.
Can a postnup waive alimony in Florida? Yes. Spouses can set, limit, or waive alimony that would be paid after a divorce. Waivers of temporary support during a pending divorce have historically not been enforced. Because a postnup can be challenged as unfair, alimony terms should be reasonable in light of each spouse’s circumstances.
Do both spouses need their own lawyer for a postnup? Florida does not strictly require it, but it is strongly recommended. A single attorney cannot represent both spouses because their interests are adverse. Independent counsel for each spouse is one of the best ways to protect the agreement from later challenges.
Can a postnup protect my business in Florida? Yes. A postnup can define the business as separate property, address how growth in value will be treated, and set valuation methods and buyout terms. This can help protect the business, its operations, and any co-owners in the event of a divorce.
Can a postnuptial agreement decide custody or child support? No. Child support is calculated under Florida’s guidelines, and time-sharing and parental responsibility are decided based on the child’s best interests at the time of the case. A postnup cannot bind the court on these issues.
Can we use a postnup to fix problems with our prenup? Often, yes. A postnup can amend or replace a prenup that has disclosure problems, execution defects, or outdated terms. The new agreement must meet the standards that apply to postnups, including fair disclosure and proper witnessing for estate waivers.
Can a postnup be signed after an affair? It can, and some couples sign postnups as part of reconciliation. Agreements signed in the middle of a marital crisis draw closer scrutiny for duress and coercion, so allowing time, providing full disclosure, and involving independent counsel are especially important. Provisions penalizing specific conduct may not be enforced as written.
Speak With a Tampa Prenup Lawyer About a Postnuptial Agreement
If you are already married and wish you had addressed financial issues before the wedding, it is not too late. A carefully drafted postnuptial agreement can provide many of the same protections as a prenup, including clarity on property, alimony, business interests, and inheritance rights.
Because Florida applies different standards to postnups, including heightened disclosure obligations and a burden-shifting test for unfair agreements, the process deserves careful attention. If you live in Tampa or elsewhere in Hillsborough County and are considering a postnuptial agreement, contact our office to schedule a consultation.
Written by Damien McKinney, Founding Partner
Damien McKinney is the Founding Partner of The McKinney Law Group Family & Divorce Lawyers, bringing nearly two decades of experience to complex marital and family law matters. He is licensed in both Florida and North Carolina and has been repeatedly recognized as a Rising Star by Super Lawyers.