Prenuptial agreements — what they're worth in England and Wales
REVIEWED BY: Sean McNamara on 2026-08-30
England and Wales is unusual: prenuptial agreements are not automatically binding. But since the Supreme Court's decision in Radmacher v Granatino (2010), a properly made prenup carries decisive practical weight in most cases. This guide explains what makes a prenup effective and where it fails. It is general information, not legal advice.
The legal position
- There is no statute making prenups binding — the governing framework is the Matrimonial Causes Act 1973's fairness criteria, applied to the facts
- In Radmacher, the Supreme Court held that a 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 it would not be fair to hold the parties to it
- In practice, a well-made prenup is upheld in the great majority of cases; the requirements are all about process and fairness
What makes a prenup effective
1. No pressure: signed at least 28 days before the wedding (the Law Commission's recommended minimum); no last-minute ambushes, no signing under duress 2. Full financial disclosure: both parties see each other's assets, incomes and liabilities before signing 3. Independent legal advice: each party has their own solicitor; a prenup signed without advice for one side is fragile 4. Fairness on needs: the agreement cannot leave one party with nothing — if it fails to meet either party's (or the children's) needs, the court will depart from it 5. Intention to be bound: drafted in contractual form with lawyers, not a DIY letter 6. Updated for changed circumstances: reviewed after children, after major wealth changes; agreements that aged badly get down-weighted
Where prenups fail
- Children: the biggest factor. An agreement made before children rarely survives unchanged where a child's welfare requires a different outcome — the primary carer's needs balloon and the court will prioritise the child over the deal
- Needs not met: if following the agreement leaves one party homeless or on benefits while the other keeps everything, it "would not be fair to hold them to it"
- No disclosure or no advice: process failures gut the Radmacher weight
- Timing: signed the night before the wedding suggests pressure
- Non-matrimonial property confusion: prenups often seek to ring-fence inherited or pre-owned wealth — which courts are sympathetic to — but mingling assets during the marriage muddies the ring-fence
Who should consider one
- Parties entering marriage with substantially unequal assets
- Second marriages — where each party wants to protect children from a first marriage
- Business owners — protecting company value and continuity
- Anyone with expected inheritance
Postnuptial agreements
The same principles apply to agreements made during the marriage (postnups) — often used after a separation scare, an inheritance, or to update a prenup after children. Courts give them similar weight, and the process requirements (disclosure, advice, fairness) are identical.
Cost and drafting
- Expect £1,500–£5,000+ for a properly drafted prenup with both parties advised — modest against what it protects
- DIY templates are dangerous: a prenup that fails process requirements costs the drafting fees and provides nothing; the value is in the process
- Review the agreement every 5 years or on major life events — put a review clause in it
If you're divorcing and there's a prenup
- Take the agreement to a solicitor early — its terms shape the financial remedy strategy
- Check its process validity (28 days? disclosure? advice?) — weaknesses are arguments
- Needs still govern the floor: even a strong prenup can't avoid provision for a spouse's genuine needs and any children
Official links
- [Radmacher v Granatino [2010] UKSC 42 (BAILII)](https://www.bailii.org/uk/cases/UKSC/2010/42.html)
- Law Commission — Marital Property Agreements report (2014)
- Prenuptial agreements (MoneyHelper)
- Find a family solicitor (Law Society)
- Money and property when a relationship ends (gov.uk)
YourFamilyCase.co.uk is an independent information directory — we are not affiliated with, endorsed by, or connected to HMCTS or gov.uk. This page is general information and is not legal advice. Prenup drafting is specialist work — use a solicitor with financial remedy accreditation.
Content verified against the official HMCTS court directory, gov.uk forms and fees pages, and the professional body registers (SRA, FMC, Bar Council). Last reviewed September 2026.