What Is a Prenup? Eight Things It Can Cover, and One It Cannot

By Nadia Pazos, Family Law Attorney, Pazos Law Group · Updated September 9, 2026

Quick Answer

A prenup — short for prenuptial agreement, and called a “premarital agreement” in the statute books — is a written contract that two people sign before they marry, setting out what happens to their property, their debts and their support obligations if the marriage ends by divorce or by death. It is not a document either of them files with a court. It sits in a drawer and does nothing until the wedding: under Fla. Stat. § 61.079(5) a premarital agreement “becomes effective upon marriage of the parties.” Florida’s statute lists eight subjects a prenup may cover, and one it may not touch.

The Eight Things a Prenup Can Cover

Section 61.079(4)(a) is an enumerated list. Parties to a premarital agreement may contract with respect to:

Property rights and obligations — in any property of either or both of them, “whenever and wherever acquired or located.”
Control of that property — the right to buy, sell, use, transfer, exchange, abandon, lease, consume, expend, assign, mortgage, encumber, dispose of, or otherwise manage it.
What happens to property on a triggering event — separation, dissolution of the marriage, death, or the occurrence or non-occurrence of any other event the parties name.
Spousal support — its establishment, modification, waiver, or elimination.
Wills and trusts — the making of a will, trust or other arrangement to carry out the agreement.
Life insurance — ownership rights in, and disposition of, the death benefit of a policy.
Which state’s law governs the construction of the agreement.
Any other matter, including personal rights and obligations, so long as it does not violate Florida public policy or a law imposing a criminal penalty.

The One Thing It Cannot Do

Section 61.079(4)(b) is a single sentence and it is absolute: “The right of a child to support may not be adversely affected by a premarital agreement.”

Two people can sign away spousal support between themselves. They cannot sign away their child’s support, because that right belongs to the child and not to either parent. A clause that tries to do it does not bind the court.

What It Takes to Make One

Less than most people expect. Section 61.079(3), headed FORMALITIES, is one sentence: a premarital agreement “must be in writing and signed by both parties,” and it is enforceable “without consideration other than the marriage itself.” The words notary, witness and acknowledge do not appear anywhere in § 61.079 — not once in the whole section.

One clause is the exception, and it catches people out. If the agreement waives what a surviving spouse would take at death, that waiver answers to the probate code instead: § 732.702(1) requires it to be signed “in the presence of two subscribing witnesses.” The notary and witness rules are set out in full here.

What a Prenup Costs to Sign

Nothing, at the courthouse. A premarital agreement is a private contract; it is never filed, so it carries no filing fee, no recording fee and no clerk’s cost. For comparison, filing a petition for dissolution of marriage costs $409.00 — the same figure at the Miami-Dade, Broward and Palm Beach clerks. Those are court fees, not attorney fees. The two numbers side by side.

When a Prenup Is Attacked

A prenup only reaches a courtroom when someone challenges it, and the burden sits on the challenger. Under § 61.079(7)(a) the party resisting the agreement must prove that it was not executed voluntarily; or that it was the product of fraud, duress, coercion or overreaching; or that it was unconscionable when it was executed and the disclosure requirements in that subsection were not met.

There is also a timing rule that surprises people. Under § 61.079(9), any limitations period on a claim under a premarital agreement is tolled during the marriage — the clock does not run while the couple is married.

What It Waives at Death

Without a valid waiver, a surviving spouse in Florida keeps three separate entitlements that stack: 30 percent of the elective estate under § 732.2065, $20,000 of exempt property under § 732.402, and an $18,000 family allowance under § 732.403. What a prenup waives at death, in detail.

Frequently Asked Questions

What does prenup mean?

It is short for prenuptial agreement: a written contract signed before marriage that sets out property, debt and support arrangements if the marriage ends. Florida’s statute calls it a premarital agreement.

When does a prenup take effect?

On marriage. § 61.079(5) provides that a premarital agreement “becomes effective upon marriage of the parties”. Signature alone does nothing, and if the wedding never happens the agreement never takes effect at all. It also means the date of signature decides which body of law applies: sign after the ceremony and it is not a premarital agreement, but a postnuptial one judged under contract principles and Casto v. Casto.

Can a prenup decide child support?

No. § 61.079(4)(b) is one sentence and it is the clearest boundary in the section: “The right of a child to support may not be adversely affected by a premarital agreement.” A waiver, a cap or a formula that reduces what a child would otherwise receive is unenforceable however carefully the rest of the document was executed. The same limit reaches custody and time-sharing, which belong to § 61.13.

Can a prenup waive alimony?

Yes. Spousal support is the fourth of the eight subjects listed in § 61.079(4)(a), and the statute names its “establishment, modification, waiver, or elimination”. One backstop survives: under § 61.079(7)(b), if enforcing the waiver would leave a spouse eligible for public assistance at separation or divorce, a court may order support sufficient to avoid that eligibility.

Does a prenup have to be notarized?

Not under § 61.079(3), which requires only that the agreement be in writing and signed by both parties. The words notary, witness and acknowledge appear nowhere in the section. A waiver of spousal death rights is governed by a different statute and is stricter: § 732.702(1) requires the waiving party to sign in the presence of two subscribing witnesses.

What is the difference between a prenup and a postnup?

Timing, and the statute that governs it. A prenup is signed before the marriage and falls under § 61.079. A postnuptial agreement is signed during the marriage and falls outside that section.

Primary Sources

Fla. Stat. § 61.079 — premarital agreements: formalities, content, effect of marriage, enforcement.
Fla. Stat. § 732.702 — waiver of spousal rights.