A prenup is a promise you make to your future self: that twenty or thirty years from now, in the worst season of your life, a court will read a document signed by two much younger people and hold everyone to it. Whether that happens is decided partly at drafting — and partly by what you do with the agreement across the decades in between. This page covers both: how Florida enforcement actually works, and the custody-of-the-document discipline that keeps an agreement provable in 2046.
How a prenup gets enforced in a Florida divorce
There is no separate "prenup court." When a dissolution is filed, the enforcing spouse pleads the agreement and asks the court to apply it — to confirm separate property, apply the agreed distribution, honor the support terms. The burden then shifts in a specific way: under section 61.079(7), the challenging spouse must prove a defense — involuntariness; fraud, duress, coercion, or overreaching; or unconscionability at signing plus the three disclosure failures (no fair disclosure, no written waiver of it, no independent knowledge). Unconscionability is decided by the judge as a matter of law. If no defense lands, the agreement controls, and the divorce becomes what the two of you designed years earlier: mostly arithmetic. Agreements signed before October 1, 2007 — and all postnups — are instead tested under Casto v. Casto, which reaches similar destinations by a slightly different route, including a burden-shifting presumption when an agreement is unreasonable on its face and disclosure was thin.
Two practical notes from the litigation trenches. First, enforcement fights are usually front-loaded: the validity of the agreement is often resolved early — by motion or a focused evidentiary hearing — because everything else in the case depends on it. Second, a well-drafted agreement makes the challenger pay for losing: Florida's Supreme Court has enforced prevailing-party fee clauses covering challenges to the agreement itself (Lashkajani), a term we build in precisely because it changes the challenger's math before they file.
The 20-year problem: an agreement is evidence, and evidence ages
Time is the silent party to every prenup. Between signing and enforcement: memories fade and improve in each spouse's favor; witnesses move and die; law firms dissolve and destroy closed files; homes flood; marriages produce children, businesses, new states, and thick layers of commingled finance on top of the clean lines the agreement drew. The enforcing spouse's job in 2046 is to produce the executed original, prove the process that made it, and show the couple lived consistently with it — or at least did not abandon it. Every element of that proof can be banked in advance:
| Threat over time | The discipline that defeats it |
|---|---|
| Original can't be found | Two duplicate originals executed at signing — one vaulted by each spouse separately (safe-deposit box, fireproof safe, or with estate documents), never both in the same house. A scanned copy in each spouse's records and in counsel's file. |
| Signing process disputed | Counsel's execution file preserved: dated drafts, transmittal emails, disclosure receipts, the signed acknowledgments, witness and notary information. Ask your lawyer their retention policy — and keep your own complete set; firms are not eternal. |
| "We tore it up years ago" | An amendment clause requiring signed, witnessed writings — so informal testimony cannot amend or revoke. Any real change is executed with full formalities; anything less is noise. |
| Schedules look ancient | They are supposed to — disclosure is judged as of signing. Keep the underlying statements and returns with the originals so the numbers can be reconstructed and defended decades later. |
| Conduct contradicts the agreement | Annual hygiene: keep separate property actually separate — titles, accounts, no casual commingling. The agreement defines the lines; your banking either honors them or slowly erases them. |
| Life outgrows the terms | Milestone reviews (new business, new state, children, inheritance received, tenth anniversary) with counsel — amend deliberately or reaffirm deliberately. A consciously maintained agreement is far harder to paint as a relic. |
Moving states: will Florida's agreement follow you?
Most American states enforce premarital agreements under the UPAA or comparable common law, and courts generally respect a choice-of-law clause selecting Florida — which section 61.079 expressly authorizes. But "generally" is doing work in that sentence: a new domicile can apply its own procedural rules and public-policy limits (a few states scrutinize support waivers more aggressively, or impose their own counsel and timing expectations). This is why our agreements are executed to the strictest common denominator — witnessed, notarized, both parties counseled, disclosure documented — so the file satisfies pickier states than Florida without knowing in advance which one you will retire to. If you relocate permanently, a brief check-in with local counsel in the new state, agreement in hand, is cheap confirmation; in rare cases a confirming amendment executed under the new state's formalities is worth the afternoon.
Death, not divorce: enforcing the estate provisions
Half of a prenup's work is done in probate, not family court. The waivers of elective share, homestead, exempt property, and family allowance under section 732.702 are enforced against a surviving spouse's claims — which is why the two-subscribing-witness execution and the reconciliation of wills, trusts, and beneficiary designations matter so much. The recurring failure: the ERISA consents that were never signed after the wedding, leaving a 401(k)'s survivor benefit payable to the spouse "who waived everything." Federal law will not care what the prenup says; only the plan-form spousal consent, signed after marriage, waives those benefits. If you administer an estate against a prenup, or you are the survivor deciding whether your own waiver holds, both analyses start with the execution file — another reason it must still exist.
Defending a challenge: what the fight actually looks like
When we defend an agreement, the case is built from the drafting file outward: the timeline exhibit (first discussion, drafts exchanged, counsel retained, signing date versus wedding date); the disclosure exhibit (schedules, transmittals, receipts); the execution proof (witnesses, notary, acknowledgments); and the conduct evidence (years of the couple living by the agreement's lines). Then the challenger's theory is taken apart element by element — because under the statute they must prove a defense, not merely narrate unhappiness with the bargain. When we attack an agreement, we hunt the same file for its gaps: the late first draft, the schedule that omitted the business's real earnings, the missing witnesses, the unrepresented spouse with no acknowledgment. Which side of that fight you will be on was decided years earlier, by how the agreement was made and kept. That is the entire thesis of this practice: enforcement is not an event — it is the harvest of process.
Common questions
The defenses are typically raised when enforcement is sought — in the dissolution or probate case — and section 61.079 tolls limitations defenses during the marriage while preserving equitable doctrines. Practically: a spouse cannot "miss the deadline" to challenge during a happy marriage, and an enforcing spouse should assume every defense remains available whenever the agreement is finally invoked. Build the file accordingly from day one.
Not necessarily — Florida evidence law allows proving a lost document's contents with copies and testimony, and a complete scan plus counsel's file often carries the day. But you have converted a clean case into a provable-with-effort case, and handed the other side an authenticity argument. If both spouses are still on good terms, the better cure is a short ratification amendment executed now with full formalities, creating fresh originals. If relations are strained, gather every copy and record immediately and talk to counsel before anyone else knows the originals are missing.
Yes — section 61.079 allows amendment, revocation, or abandonment after marriage by a signed written agreement, effective without additional consideration. The operative words are signed and written: do it with the same formalities as the original (witnesses, notary, updated schedules where relevant), and store the amendment with both originals. What you should never rely on is an oral understanding or a dramatic gesture; a shredded copy revokes nothing when a duplicate original exists.
Children do not void an agreement, but they redraw its edges: child support and time-sharing were never controllable by the contract, and a support waiver that looked fair for a two-career couple may read differently against a spouse who left the workforce to raise children. Some agreements anticipate this with milestone adjustments; where yours does not, the arrival of children is exactly the kind of event that should trigger a review-and-amend conversation — deliberately, in writing, while everyone is on the same team.
It depends almost entirely on the execution file. A well-papered agreement is often sustained early and economically — sometimes on motion — and a prevailing-party fee clause can shift the cost to the challenger. A thin file means an evidentiary fight over events from decades ago, which is where fees grow. We quote validity reviews and enforcement engagements plainly at consultation once we have seen the agreement and its history; the honest range is wide for exactly this reason.
Your agreement should outlast everything except the marriage.
Drafting, ratification, defense, and challenge — call (407) 749-1034 or request a confidential consultation.
General information about Florida law — not legal advice, and no attorney-client relationship is created by reading it. Authorities referenced include § 61.079, Fla. Stat., § 732.702, Fla. Stat., Casto v. Casto, 508 So. 2d 330 (Fla. 1987), and Lashkajani v. Lashkajani, 911 So. 2d 1154 (Fla. 2005) (verified July 2026). Every situation turns on its own facts.