What is a prenuptial agreement, and is it binding?
An agreement made before marriage setting out how assets would be divided on divorce. In England and Wales it is not automatically binding — but courts give properly made agreements substantial weight, which in practice means they usually determine the outcome.
Why they are not strictly binding. Courts retain a statutory discretion to achieve a fair outcome, which cannot be removed by contract. A leading Supreme Court decision established that the court should give effect to an agreement freely entered into with a full appreciation of its implications, unless it would not be fair to hold the parties to it.
What makes an agreement likely to be upheld:
Full and frank financial disclosure by both parties. An agreement signed without knowing what the other person owns is vulnerable.
Independent legal advice for each party, from different solicitors.
No pressure. Signed well in advance — a commonly cited minimum is at least 28 days before the wedding — since an agreement presented days beforehand invites a finding of duress.
Fairness at the time of signing and of enforcement. An agreement leaving one party in real need, or failing to provide for children, will not be upheld regardless of how it was made.
Review provisions, since circumstances change — children, illness, career sacrifice — and an agreement that anticipated none of them is more likely to be set aside.
What they cannot do: bind the court on arrangements for children, which are always decided on the child's welfare; or exclude the court's jurisdiction entirely.
Who they suit: second marriages, particularly where there are children from a previous relationship; protecting inherited or family assets; business owners with other stakeholders; substantial pre-marriage wealth disparity; and international couples, where the question of which country's law applies is itself significant.
Post-nuptial agreements, made after marriage, are treated on a similar basis.
In many other jurisdictions these agreements are straightforwardly binding, which is a common source of confusion.
General information, not legal advice; take advice specific to your circumstances.