No, Prenuptial Agreements are not legally binding, but if they are prepared properly, they can carry significant weight.
The legal principles come from the decision of the Supreme Court in 2010 (Radmacher v Granatino) where the court said: ‘The court should give effect to a nuptial agreement that is freely entered into by each party with a full appreciation of its implications unless in the circumstances prevailing it would not be fair to hold the parties to their agreement.’