Do Prenups Expire? Sunset Clauses and the 10-Year Myth, Explained

You heard somewhere that a prenup stops working after ten years, and now you are wondering whether the agreement you signed, or the one you are thinking about signing, quietly has a shelf life. It does not. A prenup does not expire on its own after any number of years. It takes effect the day you marry and stays in force for the entire marriage unless the document itself sets an end date, both partners revoke it in writing, or a court declines to enforce it. The Uniform Law Commission, which drafted the model law most states follow, built the framework this way: enforceability turns on how the agreement was made, not on how old it is. Twenty-nine states plus the District of Columbia have adopted a version of that model, the Uniform Premarital Agreement Act.

Three different ideas tend to get tangled together here: whether a prenup expires naturally (it does not), whether you can choose to make it expire (you can, with a sunset clause), and whether an old prenup can become harder to enforce (a separate question with its own answer). Let's take them one at a time.

Do prenups expire on their own?

No. A prenup takes effect at marriage and runs until divorce, death, a written revocation signed by both partners, or a court setting it aside. There is no built-in clock. Nothing in the standard statutory framework causes an agreement to lapse because a certain number of anniversaries have passed.

The reason is baked into the law. Under the Uniform Premarital Agreement Act as states have enacted it, a premarital agreement becomes effective upon marriage and remains binding from that point forward. The statutes describe how an agreement is formed, how it can be revoked, and when a court may refuse to enforce it. None of them includes an expiration date. A prenup is designed to sit quietly in force, often unread, until the day its terms are needed.

This is also why a prenup is a planning tool rather than a document you file and forget to renew. The terms you agree on now are the terms that apply later, which is the point of writing them down together while you both have time and full information. Rules on formation and enforcement are set by state law, and they vary, so it helps to understand how prenuptial agreements differ across states before you assume your state works like your neighbor's.

Are prenups void after 10 years?

No. No state statute automatically voids a prenup at the ten-year mark, or at any other anniversary. A properly made prenup is as valid at year ten as it was at year one. This is one of the most common myths about prenups, and it is worth saying plainly: there is no ten-year rule.

You can see this in the statutes themselves. Nevada's version of the law, Nevada Revised Statutes Chapter 123A, sets out how a premarital agreement is formed, how it is amended or revoked, and the grounds on which a court may decline to enforce it. There is no provision that makes the agreement expire with time. The same is true of other states that follow the model law. The absence is not an oversight; the framework was designed so that an agreement endures unless the parties end it or a court finds a defect in how it was made.

So where does the myth come from? A few places. Some couples write sunset clauses that happen to use ten years as a milestone, and the specific choice gets mistaken for a universal rule. Others confuse spousal support rules that treat long marriages differently with the prenup itself. And plenty of it is just repetition: a plausible-sounding rumor that spreads because nobody checks the statute. Here is what people tend to believe versus what the law actually does.

What is a sunset clause, and how does it work?

A sunset clause is an optional provision that makes a prenup, or specific parts of it, expire after a set number of years or at a chosen event. It is the one way a prenup gets an end date, and it only happens because both partners agreed to write it in. No automatic expiration, no ten-year rule, no required renewal: an expiration exists only when you deliberately add one.

The time frames couples pick vary. Some choose ten years, others fifteen or twenty; the number is a design choice, not a legal default. Instead of a fixed period, a sunset clause can also be tied to an event, like the birth of a child or a wedding anniversary. When the clause triggers, the affected terms stop applying and default state law takes over for those matters. If you want to see what that default looks like, our guide to what happens if you don't have a prenup walks through how state law divides property and handles support when no agreement controls.

Sunset clauses also come in more than one shape. Here are the common forms.

The phased approach is worth noting, because it shows how much control couples have. A spousal support waiver might expire after ten years while terms protecting a premarital business stay in force longer. The language in the agreement controls exactly what expires and when.

Why would a couple choose a sunset clause?

Couples choose a sunset clause when they want the protection of a prenup now but not necessarily forever. It is a planning choice partners make together, and it tends to serve two purposes. The first is reassurance. A partner who feels uneasy about signing may find it easier to say yes to an agreement that winds down after the marriage has proven itself over a decade or two. The clause signals that the terms are meant for an early, uncertain chapter, not a permanent verdict on the relationship.

The second purpose is fairness over time. Terms that make sense at the start of a marriage can feel lopsided after many years, shared sacrifices, and a life built together. A sunset clause lets a couple keep certain protections for a defined window and then return to default state law once circumstances have changed. Fairness in a prenup is generally evaluated as of signing, and in some states it can be revisited at enforcement, which is a theme we cover in our guide to whether your prenup is actually fair. Building in a sunset or review provision is one way couples address that concern on purpose, rather than hoping a court will.

A sunset clause is a deliberate decision, not a loophole. The couples who use one have thought about where they want the agreement to end, and they have written that choice into the document together.

What can make an older prenup harder to enforce?

Time alone does not make a prenup harder to enforce, but certain defects can, and some of them only surface years later. The grounds a court looks at trace back to how the agreement was made, not to its age. Under the enforcement provisions of the Uniform Premarital Agreement Act, a court may decline to enforce an agreement if it was not signed voluntarily, if it was unconscionable (so one-sided or unfair that a court will not uphold it) and a partner did not receive or waive fair financial disclosure, or if similar process problems tainted the signing.

You can see these grounds laid out in North Carolina General Statutes Chapter 52B, which requires a premarital agreement to be in writing and signed by both parties and sets out when a court may refuse to enforce it. None of the listed grounds is elapsed time. A rushed signing, pressure on a reluctant partner, or hidden assets at the outset can undermine an agreement whether it is challenged in year two or year twelve. The defect was there from the start; it just took a divorce to bring it to light. Our checklist on what makes a prenup enforceable covers the signing practices that keep an agreement sound.

There is one wrinkle worth flagging. A few states let a court consider whether enforcing a prenup would cause substantial hardship because of a material change in circumstances since signing. West Virginia is one example; its enacted version of the law, West Virginia Code § 48-1A-601, includes such a provision. This may matter in those states, framed carefully: it is not a universal rule, and it is not the same as the agreement expiring. The agreement stays in force; a court simply may weigh how fair it has become. In most states, the fairness inquiry stays anchored to the moment of signing.

When do couples revisit a prenup?

Couples tend to revisit a prenup when their life changes in a way the original terms did not anticipate: a new business, a move to a different state, a child, a large inheritance, or a shift in who earns what. The agreement does not require review, but major milestones are natural moments to check whether the terms still reflect your shared plan. Thinking of a prenup as something you can revisit, rather than a sealed decision, tends to make couples more comfortable with it in the first place.

Changing an agreement after marriage has its own rules. Under the Uniform Premarital Agreement Act, once you are married, a prenup can be amended or revoked only by a written agreement signed by both partners. A conversation, a handshake, or a note in a drawer will not do it. We cover the mechanics of amendment and revocation in detail in our guide to whether a prenup is a living document, so we will not duplicate them here.

Some couples reach a point where they would rather replace the framework entirely than tweak it, which raises the question of a postnuptial agreement. If that is where you are, our comparison of a prenup versus a postnup explains how the two differ. First is building a postnup product, and married couples can join the First Postnup early-access list, but for anything you need now, consult independent legal counsel about a postnuptial agreement.

Frequently Asked Questions

Do prenups expire after a certain number of years?

No. A prenup does not expire on its own after any number of years. It takes effect when you marry and stays in force for the whole marriage unless it contains a sunset clause that sets an end date, both partners revoke it in writing, or a court declines to enforce it.

Are prenups void after 10 years?

No. No state statute automatically voids a prenup at ten years. The myth likely spreads because some sunset clauses use ten years as a milestone, and because a few people confuse long-marriage spousal support rules with the prenup itself. A properly made prenup is as valid at year ten as at year one.

What is a sunset clause in a prenup?

A sunset clause is an optional provision that makes a prenup, or specific parts of it, expire after a set period or at a triggering event. Common choices are 5, 10, 15, or 20 years of marriage, or an event like the birth of a child. When it triggers, default state law takes over for those terms.

Can only part of a prenup expire?

Yes. A phased or staggered sunset clause lets different provisions end on different schedules. For example, a spousal support waiver might expire after ten years while terms protecting a premarital business stay in force longer. The exact language in the agreement controls what expires and when.

Does a prenup end after divorce or death?

A prenup does not expire before those events; it is designed to take effect at divorce or death. Its terms guide how property, debts, and support are handled once the marriage ends. Until one of those events, a valid prenup sits in force, often unread.

Can an old prenup still be challenged?

Yes, but time alone is not the reason. Courts may decline to enforce a prenup over how it was signed, such as pressure, a rushed deadline, or missing financial disclosure, or, in some states, because enforcing it now would be unconscionable after a major change in circumstances.

How First helps

A prenup should not surprise you years later, whether by expiring when you thought it was permanent or by lasting when you assumed it had lapsed. The way to avoid that is clear, deliberate terms you chose on purpose. If you want a prenup whose terms are spelled out plainly, including whether to build in a sunset or review provision, First lets couples draft one online, on your own timeline, with no PDFs and no hourly rates. You set the terms now, with full information and time to decide what should last and what should wind down.

Methodology

These figures are drawn from the Uniform Law Commission's enactment record for the Uniform Premarital Agreement Act and its 2012 update, the Uniform Premarital and Marital Agreements Act, together with the enacted statutes of individual states (for example, Nevada Revised Statutes Chapter 123A and North Carolina General Statutes Chapter 52B), reviewed as of 2026.

Sources

First is not a law firm. The information and tools provided by First on this site are not legal advice and not a substitute for the advice of an attorney.