Tying the knot… and untangling it: the importance of transparency in prenups

Many people assume a prenuptial agreement guarantees financial protection, but the recent court of appeal decision in Helliwell v Entwistle highlights just how crucial full financial disclosure is for these agreements to hold up in family law courts.

When significant assets are hidden – as in this case, where 73% of wealth went undisclosed – the agreement can be set aside. This ruling offers important lessons for anyone considering a prenup or facing a divorce.

Helliwell v Entwistle

The court of appeal’s judgment in Helliwell v Entwistle has reinforced that prenuptial agreements are only as strong as the financial disclosure underpinning them.

This high-profile case, livestreamed in March 2025, concerned a prenup signed on the day of the wedding between Jenny Helliwell and Simon Entwistle. The agreement stated that neither party would make financial claims against the other in the event of divorce. At the time, Ms Helliwell disclosed assets valued at around £6m.

Following their separation in 2023, Mr Entwistle sought financial remedy of £2.5m. The high court initially upheld the agreement, awarding him just £400,000 – a figure later reduced following a costs order. This sum was also less than a prior offer Ms Helliwell had made to settle.

Mr Entwistle appealed, arguing that the prenup was fundamentally flawed because Ms Helliwell failed to disclose substantial assets, including significant business interests, which he claimed brought her total wealth to over £70m. The court of appeal agreed, finding that about 73% of her assets had been deliberately withheld, seriously undermining the agreement’s validity.

The danger of deliberate non-disclosure

The court of appeal strongly criticised Ms Helliwell’s conduct, describing her non-disclosure as deceitful and “undoubtedly deliberate.” Citing the landmark case Radmacher v Granatino, the court reaffirmed that prenuptial agreements require full, frank and honest financial disclosure to be enforceable. While parties may decide the scope of disclosure, this cannot be used to mask a misrepresentation of their true financial position.

The court was clear: intentionally hiding significant assets strikes at the core of any nuptial agreement’s validity. As the agreement was based on false financial information, it was set aside. The case has now been returned to the high court for a full rehearing, with Mr Entwistle’s claims to be considered as if no prenup existed.

Key lessons for those considering a prenup

This case offers vital warnings for anyone entering into a nuptial agreement. First, transparency is essential: any attempt to conceal assets or mislead the other party risks serious legal and financial consequences.

Second, timing matters. Signing a prenup on the wedding day is far from ideal. Agreements should be finalised well before the wedding, allowing both parties time to seek independent legal advice and make informed decisions.

Our expert family lawyers can advise on prenuptial and postnuptial agreements, as well as financial remedy proceedings for clients considering a nuptial agreement or facing financial issues following a relationship breakdown.