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Post-nuptial Agreement

Also known as: Postnup, Postnuptial Agreement

Definition

A post-nuptial agreement is a written contract created after marriage that sets out how a couple will divide their assets, property, and finances if they divorce or separate.

These agreements allow married couples to protect specific assets (like inheritances or businesses) and provide financial certainty if the marriage ends, while working alongside wills to ensure assets pass to intended beneficiaries.

What Does Post-nuptial Agreement Mean?

A post-nuptial agreement (also called a postnup) is a written agreement made after marriage or civil partnership that sets out financial arrangements on divorce or separation. While not automatically binding in England and Wales, these agreements carry decisive legal weight when properly executed. Following Radmacher v Granatino (2010), courts uphold post-nuptial agreements provided both parties entered freely with full financial disclosure, independent legal advice, and the outcome isn't unfair. Under the Matrimonial Causes Act 1973, courts retain jurisdiction over financial matters but generally follow properly executed agreements.

Common triggers include receiving significant inheritance, starting a business during marriage, blended family formation, or reconciliation after separation. The agreement can cover division of property, savings, investments, pensions, business interests, inherited assets, and spousal maintenance. However, it cannot include child custody or child maintenance—UK courts always decide these based on the child's best interests at divorce, regardless of prior agreement. Including such provisions may invalidate the entire agreement.

The process requires both parties to provide full financial disclosure, each obtaining independent legal advice from separate solicitors, and both signing voluntarily. Sarah inherited her family's £850,000 farm five years into marriage and created a post-nuptial agreement with husband Tom specifying the farm remains her separate property to pass to her three children. Tom received independent legal advice, understood he was giving up a potential claim to half the farm's value, and signed voluntarily—giving the agreement strong legal weight.

Post-nuptial agreements work alongside wills and trusts in estate planning to ring-fence family wealth for blood relatives or children from first marriages, protect business ownership, and ensure bequests pass as intended. Courts retain discretion to depart from agreements if circumstances change significantly—such as major illness or substantial financial changes. Agreements should be reviewed after major life events to ensure they remain fair.

Common Questions

"When would I need a post-nuptial agreement?" You might need one after receiving significant inheritance, starting a business during marriage, or when one spouse's financial situation changes dramatically. They're also common when couples reconcile after separation and want to protect certain assets.

"Is a post-nuptial agreement legally binding in the UK?" Not automatically, but courts give them decisive weight if properly executed. Following Radmacher v Granatino (2010), courts uphold agreements entered freely with full financial disclosure, independent legal advice for both parties, and no unfairness at divorce.

"Can a post-nuptial agreement cover child custody and maintenance?" No, post-nuptial agreements cannot predetermine child custody or child maintenance. UK courts always decide these based on the child's best interests at divorce, regardless of prior agreement. Including such provisions may invalidate the entire agreement.

Common Misconceptions

Myth: Post-nuptial agreements aren't worth having because they're not legally binding

Reality: While not automatically binding in England and Wales, post-nuptial agreements carry decisive legal weight when properly executed. Since Radmacher v Granatino (2010), courts uphold agreements unless unfair, provided both parties entered freely with full financial disclosure and independent legal advice.

Myth: You can use a post-nuptial agreement to decide who gets custody of the children

Reality: Post-nuptial agreements cannot include child custody, residence arrangements, or child maintenance provisions. UK courts always determine these based on the child's best interests at divorce, regardless of prior agreement. Including such clauses may invalidate the entire agreement.

  • Pre-nuptial Agreement: The alternative created before marriage rather than after—both receive identical legal treatment under Radmacher principles.
  • Marriage: The foundational relationship that creates the legal context for post-nuptial agreements to exist and operate.
  • Second Marriage: A common scenario where post-nuptial agreements protect children from first marriages while building new relationships.
  • Divorce: The event when post-nuptial agreements come into effect and influence court decisions on financial settlements.
  • Protecting Children from First Marriage: The primary use case where post-nuptial agreements ensure assets pass to intended beneficiaries from previous relationships.
  • Contract: The legal form that post-nuptial agreements take, with specific enforceability rules under family law.

Need Help with Your Will?

Understanding post-nuptial agreements matters for comprehensive estate planning. If you've created or are considering a post-nuptial agreement, ensuring your will reflects these arrangements protects your intended beneficiaries and prevents conflicts between documents.

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Legal Disclaimer:

This article provides general information only and does not constitute legal or financial advice. WUHLD is not a law firm and does not provide legal advice. Laws and guidance change and their application depends on your circumstances. For advice about your situation, consult a qualified solicitor or regulated professional. Unless stated otherwise, information relates to England and Wales.