The rise in prenuptial agreements isn’t simply about couples expecting divorce – it’s increasingly being driven by Britain’s Great Wealth Transfer, as younger generations inherit property, businesses and investment portfolios earlier than ever before. Alistair Myles explains why family wealth is becoming one of the biggest drivers behind modern prenups and looks at the crossover with private client.
For many couples, the conversation around a pre-nuptial agreement has traditionally centred on what each person is bringing into a marriage. Increasingly, however, the more important question is what one or both parties may inherit before or during the marriage.
Britain is entering a significant inter-generational transfer of wealth, with property, family businesses and investment portfolios moving between generations. For family and private client lawyers, this is creating a new dynamic: pre-nups are no longer simply being used by wealthy individuals to protect fortunes they have already accumulated, but by families seeking to preserve wealth for future generations. Post-nups have also risen in popularity for the same reason.
There is a clear reason for this shift. Older generations have accumulated significant wealth through rising property values and long-term investment, while inheritance tax and concerns about how that wealth will be preserved are encouraging families to think more carefully about succession planning. At the same time, younger generations are facing high property prices and financial pressures in their twenties and thirties.
Keeping it in the family
This creates a tension for families: how can wealth be passed down during a parent’s or grandparent’s lifetime, while maintaining the intention that it remains within the family?
For some families, trusts and wider private client structures will provide the answer. But where substantial wealth is being transferred to a child who is entering, or already in, a marriage, the pre-nuptial agreement can become an important additional layer of protection.
This is particularly relevant where the anticipated inheritance is a family home, business or investment portfolio. A future inheritance is inherently different from an existing bank balance: its value, ownership and use may change over time. A family property may become the couple’s home; a business may require the involvement of both spouses; investments may be sold or reinvested.
That makes the drafting and advice around these agreements increasingly nuanced. The question is not simply whether an asset originated with one family, but how it is intended to be treated throughout the marriage.
The legal intersection
This distinction has become particularly relevant following the Supreme Court’s judgment in Standish v Standish [2025] UKSC 26. The court confirmed that non-matrimonial property is not subject to the sharing principle, while also recognising that property which begins as non-matrimonial can become matrimonial depending on how the parties treat it over time.
The judgment emphasised that the source of an asset remains important, but that the parties’ treatment of it can be critical to whether it becomes matrimonialised.
For advisers dealing with anticipated inheritances, this reinforces the value of addressing intentions at an early stage. A pre-nup or post-nup cannot remove the court’s discretion or guarantee a particular outcome, but a carefully prepared agreement can provide evidence of the parties’ intentions and set out a framework for how particular assets are intended to be treated.
It also highlights why these matters increasingly sit at the intersection of family and private client work. A pre-nup concerning a future family business may require an understanding of corporate structures; an investment portfolio may involve tax and investment advice; and a wider succession plan may involve trusts or other estate-planning structures.
Succession and separation
The changing wealth landscape does not necessarily mean reinventing the pre-nup. The fundamental purpose remains the same: providing greater certainty in circumstances where the parties want to agree how their financial affairs should be treated if the marriage ends.
What is changing is the context in which those agreements are being made. Increasingly, the person sitting in front of the family lawyer is not simply seeking to protect the wealth they have earned, but wealth that their parents or grandparents intend to pass down.
The next generation of pre-nups may therefore be as much about succession as separation. As families become more deliberate about how wealth is transferred, family lawyers will increasingly find themselves working alongside private client, tax and corporate advisers to ensure that the intentions behind that transfer are understood across the family’s wider wealth-planning strategy.
The law may not yet provide the certainty that some families would ideally like. But as the Great Wealth Transfer gathers pace, the demand for clearer rules around matrimonial and non-matrimonial wealth is likely to grow – and so too will the role of the pre-nup in keeping generational wealth within the family.
About the author
Alistair Myles is a specialist family law solicitor with extensive experience in complex financial and children matters, including cases involving international assets, business interests and pre- and post-nuptial agreements. He has acted in a number of cases that have helped shape family law, including Jones v Jones and Haley v Haley. Alistair is a strong advocate of non-court dispute resolution, including mediation and family arbitration, and is recognised as a leading individual by the Legal 500, Chambers & Partners and Chambers HNW.
