Family Law Insights: Pre-Nuptial Agreements – The Dangers of Non-Disclosure

John Randle, Head of Family Practice

John is a specialist family solicitor with over 40 years’ experience dealing with complex, high value divorce cases.

On 31 July 2025, the Court of Appeal delivered a significant judgment on when pre-nuptial agreements can be set aside due to one party failing to give full financial disclosure. In Helliwell v Entwistle [2025] EWCA Civ 1055, three senior Appeal Judges allowed the husband’s appeal against an earlier ruling that upheld a pre-nuptial agreement (PNA) signed on the couple’s wedding day in the Seychelles.

At the time, the wife’s wealth was estimated between £60-70 million, while the husband’s assets were around £850,000. The PNA provided that each party would keep their “separate property” (assets owned before marriage) and that any jointly owned property would be divided equally.

However, a key clause in that PNA stated that both parties had “fully and frankly disclosed” their financial resources before signing and that their disclosure was “substantially complete in all material respects.”

Three years later, the marriage ended with no children. It was subsequently found that while the wife had disclosed assets worth about £18 million before signing the PNA, she had failed to reveal additional business and property assets worth nearly £48 million.

The judge in the first court ruling, Mr Justice Francis, upheld the PNA and awarded the husband only £400,000 (two years’ rent plus £100,000 annual income). The husband took the matter to the Court of Appeal, which delivered its verdict on 31 July 2025.

The legal framework surrounding pre-nups and post-nups

The Court of Appeal reviewed the established principles from Granatino v Radmacher [2010] UKSC 42, which remains the test for any court considering pre- and post-nuptial agreements. Following this, courts apply a two-stage test:

1. Vitiating factors: Does the agreement suffer from duress, fraud, misrepresentation, undue pressure, exploitation of a dominant position, or other unconscionable conduct?
2. Fairness: If no such factors exist, the court should give effect to an agreement freely entered into with full appreciation of its implications, unless it would be unfair to do so.

What the decision in Helliwell means for the law of pre and post nups

With respect to the above, the Appeal judges were clear to inform practitioners and parties alike that their decision in Helliwell did not change the law on pre and post nuptial agreements. Rather, the Court found the wife’s failure to disclose her substantial assets was fraudulent. Her deliberate non-disclosure of assets was, the Court ruled, a misrepresentation that violated the PNA’s declaration of “full and frank disclosure”, deliberately depriving the husband of information he was entitled to receive prior to signing. As a result, the PNA was set aside.

The case was sent back to the lower court to determine the husband’s financial claims under section 25 of the Matrimonial Causes Act 1973, without reference to the agreement. The wife was also ordered to pay his legal costs for both hearings.

Commentary

Pre-nuptial (and post-nuptial) agreements are increasingly common and are no longer limited to high-net-worth couples. They can be a valuable part of wedding and financial planning, but only if drafted and executed correctly.

Full and accurate disclosure is essential. Any failure, especially deliberate concealment, risks invalidating the agreement and may lead to costly litigation.

If you are considering a pre-nuptial agreement, or are being asked to sign one, it is important seek specialist legal advice to ensure it is properly prepared and stands the best chance of being upheld.