Are Prenuptial Agreements Legally Binding in the UK?
Many couples are surprised to learn that prenuptial agreements don’t automatically carry full legal weight in England and Wales. Unlike in some other countries, signing a prenup here does not, on its own, make it legally binding.
That doesn’t mean they should be dismissed. In fact, the way courts approach prenuptial agreements has developed considerably over the past decade. With the right preparation, a well-drafted agreement can carry significant influence in protecting your financial interests.
In this guide, we explain how UK law views prenuptial agreements, what factors the courts take into account, and the practical steps you can take to give your prenup the strongest chance of being upheld.
A Brief Introduction to Prenuptial Agreements
A prenuptial agreement is a way for couples to set out clear financial arrangements before entering into marriage or a civil partnership. Rather than being a sign of mistrust, it provides a practical framework for how assets would be divided if the relationship were to break down, helping to reduce uncertainty and potential conflict in the future.
Many couples find that discussing a prenup can actually bring them closer as it encourages open and honest communication about finances, from existing assets and debts to inheritance and future earnings, that might otherwise be difficult to raise.
By addressing these matters before marriage, couples often gain peace of mind, shared understanding, and realistic expectations about their financial future together.
Are They Legally Binding?
The way prenuptial agreements are treated in England and Wales changed significantly after the landmark Supreme Court case of Radmacher v Granatino in 2010. Although prenups are not automatically legally binding, this ruling reshaped how courts view them.
Before Radmacher, prenuptial agreements carried little weight in divorce proceedings. However, after the case, the Supreme Court’s judgment established that, provided an agreement was entered into freely and with full understanding, the courts should generally uphold it – unless doing so would be unfair.
This means that a well-prepared prenup can now have substantial influence. Courts will often give them decisive weight when dividing assets, so long as certain criteria are met. It reflects a recognition that adults should have the freedom to make decisions about their own financial arrangements.
That said, the court always retains the power to step in. If circumstances have changed dramatically since the agreement was signed, or if sticking to it would cause serious unfairness to one partner or to any children, the court can decide not to follow it.
Key Requirements for an Enforceable Prenup
For a prenuptial agreement to stand up in court, certain key requirements must be met. If these steps aren’t followed, the agreement could be dismissed.
The essentials for a valid prenup include:
Independent legal advice – each partner must have their own solicitor. This ensures both fully understand the terms and their legal rights.
Full financial disclosure – both must provide a complete picture of assets, debts, income, and inheritance expectations.
Appropriate timing – the prenup should be signed well before the wedding (at least 21 days in advance) to avoid any suggestion of rushed or pressured decisions.
Voluntary agreement – both parties must enter into the agreement freely, without coercion from their partner, family, or circumstances.
Children’s welfare protected – prenups cannot predetermine arrangements for children, as the court will always prioritise their best interests.
Meeting these requirements greatly increases the likelihood that a prenup will carry weight in court and provide the protection intended.
How Can They Be Amended?
As life changes, prenuptial agreements will need to be updated to reflect new circumstances. Career changes, inheritances, or significant shifts in finances can all be reasons for reviewing an existing agreement.
Any changes must be made with the agreement of both partners; one person cannot alter a prenup on their own. In most cases, updates are formalised through a postnuptial agreement, which follows the same legal principles but applies once a couple is already married.
As with the original prenup, both parties will need to take fresh independent legal advice to ensure they fully understand the implications of any amendments. Updated financial disclosure is also required, so both partners have a clear and current picture of each other’s circumstances.
The revised agreement must be properly drafted, signed, and executed with the same formalities as before. Informal or verbal agreements will not be enforceable.
It’s also important to note that postnuptial agreements may face closer scrutiny from the courts, given that they are made within an existing marriage.
What Cannot be Included in a Prenup
While prenuptial agreements can cover many financial matters, there are clear limits under UK law. Knowing what cannot be included helps ensure your agreement is valid and taken seriously by the courts.
What a prenup cannot do:
Decide child arrangements in advance – issues such as custody and child maintenance cannot be set out in a prenup. The court will always make decisions about children based on their best interests at the time of separation, not on earlier agreements.
Include lifestyle clauses – provisions about personal appearance, social activities, household chores, or other private aspects of married life are not legally enforceable. These fall outside the scope of what a prenup is designed to cover.
Cause serious financial hardship – while a prenup can limit spousal support, the courts will not uphold terms that leave one partner in real financial difficulty. Basic needs must still be met.
Encourage divorce or separation – any clause that could be seen as incentivising a breakup goes against public policy and will not be enforced. Prenups are intended to offer clarity and protection, not undermine the relationship.
By staying within these boundaries, couples can create an agreement that is more likely to be respected by the courts if it is ever needed.
Can You Write Your Own Prenup?
Although it is legally possible to draft your own prenuptial agreement, doing so carries significant risks that often outweigh any short-term savings. Family law is complex, and even a simple mistake can make an agreement unenforceable.
Without expert guidance, it’s easy to include terms the court will not uphold or to leave out key provisions altogether. In some cases, a poorly drafted agreement can leave both parties in a worse position than if no prenup had been made at all.
Courts need to be satisfied that both partners understood what they were agreeing to. Without solicitors involved, there’s always a risk the agreement could be set aside, even if it seemed fair at the time.
DIY prenups also tend to favour the partner who drafted them, creating an imbalance that can signal to the court that the agreement was not reached fairly or equally. This greatly increases the likelihood of it being overturned.
By working with an experienced family law solicitor, you can be confident that your prenup is properly structured, legally compliant, and tailored to your circumstances. Seen in this light, professional drafting is not an unnecessary expense but a sensible safeguard for your financial future.
When Courts Might Override a Prenup
Even with careful drafting, prenuptial agreements are not immune from being challenged.
A prenup may be overturned if:
There was coercion, fraud, or lack of capacity – If one partner was pressured, faced ultimatums, or did not have the mental capacity to fully understand what they were signing, the agreement will not stand.
Financial disclosure was incomplete – Hiding assets, debts, or income prevents true informed consent. Courts treat this very seriously and often invalidate agreements where full and honest disclosure wasn’t made.
Circumstances have changed significantly – Life events such as disability, a major change in earning ability, or the arrival of children with particular needs may justify the court departing from the original terms to avoid unfairness.
Procedural requirements weren’t met – If there was no independent legal advice, insufficient time for reflection, or if the agreement wasn’t properly executed, the prenup may be set aside.
The terms are manifestly unfair – While prenups don’t need to split assets equally, provisions that cause genuine hardship or are considered unconscionable will not be upheld.
Understanding the circumstances in which a court may set aside a prenup will help couples, with the guidance of their solicitors, draw up clearer, stronger agreements and set realistic expectations about their limits.
Expert Prenup Guidance with RJS Family Law
Prenuptial agreements can bring clarity and peace of mind. While not automatically binding in England and Wales, a well-prepared prenup that follows the right legal steps can carry real weight in court, helping couples move forward with confidence.
At RJS Family Law, we guide couples through the process with care and expertise. From financial disclosure to legal advice, we make sure every detail is covered. Contact us today.
FAQs
-
If you divorce without a prenup in place, your financial settlement will be decided according to UK family law. The court will consider factors such as the length of your marriage, the needs of both parties (especially if children are involved), and the assets available. Without a prenup, there is no prior agreement to guide this process, so the court has wide discretion to divide assets fairly.
-
Once you’re married, you can no longer sign a “prenup,” but you can enter into a postnuptial agreement instead. This works in a very similar way and sets out how assets should be divided if the marriage breaks down. Postnups are often used when couples want the same protection as a prenup but didn’t have one drawn up before their wedding.
-
Prenups are designed to deal with what happens on divorce, not death. If one spouse passes away, the distribution of their estate will usually be governed by their will or, if there is no will, by the intestacy rules.
-
The main difference lies in timing: a prenup is agreed and signed before marriage, while a postnup is signed after the wedding. Both serve the same purpose: to set out how finances and assets should be handled if the relationship ends, and both can provide clarity and reduce conflict in the event of divorce.
-
A prenup can protect assets you bring into a marriage, such as property, savings, business interests, or inheritances. It can also set out how joint assets, debts, and future earnings should be dealt with. While the courts will still review prenups for fairness, a well-drafted agreement can give you more certainty and control over your financial future.