What Is a Prenuptial Agreement?

A prenuptial agreement is a legal contract signed by two people before they marry that defines how assets, debts, and financial rights will be handled if the marriage ends. Before talking to an attorney or deciding whether to pursue one, understanding what a prenup actually is, what it changes about what Florida law would otherwise provide, and who typically uses one — and why — makes every subsequent conversation more productive.

Prenuptial agreements are not a prediction that the marriage will fail. They are a planning document — one that gives both spouses control over financial outcomes rather than leaving those outcomes entirely to a legal framework neither of them designed.

What Florida Law Provides Without a Prenup

When a marriage ends in Florida without a prenuptial agreement in place, the state’s equitable distribution framework governs how assets and debts are divided. Equitable distribution treats most assets acquired during the marriage as marital property — subject to division between both spouses — regardless of whose name is on the account or whose income funded it.

Florida law also allows courts to award alimony based on one spouse’s need and the other’s ability to pay, taking into account the length of the marriage and each spouse’s financial circumstances. Additionally, Florida’s elective share statute gives a surviving spouse the right to claim a portion of the deceased spouse’s estate even if the will directs otherwise.

A prenup does not create new rights — it modifies or replaces the defaults the law would otherwise impose.

What a Prenuptial Agreement Actually Does

Defining Separate vs. Marital Property

A prenup can specify which assets each person brings into the marriage and establish that those assets — including any appreciation — remain that person’s separate property. It can also define how property acquired during the marriage is treated: whether it becomes joint marital property or stays separate depending on how it is titled or funded.

Addressing Alimony

Spouses can agree in advance to waive alimony entirely, cap the amount or duration, or establish a formula tied to the length of the marriage. Florida courts will enforce these provisions — with one exception: an alimony waiver will not be enforced if doing so would leave one spouse dependent on public assistance.

Protecting Business Interests

For anyone who owns a business before the marriage, a prenup is one of the most direct ways to prevent a divorce from affecting that business. Without one, the value of the business — and its growth during the marriage — may be treated as a marital asset. A prenup can establish that the business remains separate property regardless of how long the marriage lasts.

Allocating Debt

A prenup can protect one spouse from liability for the other’s pre-marital debt and establish that debts taken on during the marriage by one spouse do not automatically become the other’s responsibility.

Estate and Inheritance Planning

In second marriages and blended family situations, a prenup is frequently used alongside estate planning documents to protect each spouse’s children from prior relationships. Without one, the elective share statute can override a will’s provisions in ways the deceased spouse never intended.

What a Prenup Cannot Do

A prenuptial agreement cannot address child custody or child support. Courts retain full authority over both at the time of divorce, based on the child’s best interests — not on what the parents agreed to before they were married. Any provision in a prenup that attempts to predetermine custody or waive child support is unenforceable.

A prenup also cannot include illegal provisions or clauses that create a financial incentive to divorce.

Who Uses Prenuptial Agreements & Why

The common assumption is that prenups are for wealthy people protecting large estates. In practice, they are used across a much wider range of circumstances:

• Business owners protecting an existing operation or future growth
• Individuals entering a second marriage with children, property, or retirement assets from the first
• People with significant debt — student loans, business liabilities — who want to protect their future spouse from inheriting that exposure
• Anyone with an inheritance expectation who wants to ensure that inherited assets remain in the family

The common thread is not wealth — it is the desire to make deliberate decisions about financial outcomes rather than leaving them to default legal rules.

The Difference Between a Prenup and a Postnuptial Agreement

Timing Is the Only Structural Difference

A postnuptial agreement serves the same function as a prenup but is signed after the marriage has occurred. Florida courts apply the same enforceability standards to both. If a couple did not execute a prenup before the wedding — or if circumstances have changed significantly since they married — a postnuptial agreement provides a path to the same protections.

The right time to address a prenup is well before the wedding date. Agreements signed under time pressure, or presented at the last moment, face greater scrutiny if they are later challenged.