What Is a Barder Event? The Barder Principle Explained Simply
A Barder event is a major, unforeseen change after a financial order is made that may allow someone to ask the court to look at it again. Here is the Barder principle in plain English.
Few people have heard of a Barder event until something unexpected happens after a financial order. This guide explains the Barder principle in plain English.
This article shares general community observations. It is not legal advice. The Barder principle is technical and time-sensitive, so please speak to a qualified legal professional about your own case.
Barder event in simple terms
A Barder event is a new event that happens after a financial order has been made and that is so significant it undermines the basis on which the order was made. The name comes from a well-known case, Barder v Barder (Caluori intervening) [1988] AC 20.
What are the usual ideas behind the principle?
People discussing the Barder principle commonly refer to a number of features. In broad terms:
- A new event has happened that invalidates the assumptions the order was based on.
- It happened soon after the order, not years later. In the case itself the time was described as a matter of months, not years.
- It was not foreseen or could not reasonably have been predicted. This is not one of the four conditions in the Barder judgment, but commentary treats it as a hurdle that defeats many applications.
- The person asking has acted promptly, without unreasonable delay.
- Third parties are not unfairly affected, such as someone who has bought a property in good faith.
All of these points are matters for the court, and each case turns on its own facts.
Since October 2016 an application of this kind is normally made as a set-aside application under Family Procedure Rules rule 9.9A, rather than as an appeal for permission to appeal out of time, which is how many older cases describe it.
Examples people often discuss
- A person who was expected to live for a long time dies unexpectedly soon after the order.
This is an illustration only. It does not mean a similar situation will have the same outcome. The Supreme Court has also held, in Hasan v Ul-Hasan (2023), that a Barder set-aside application can still be decided after one of the parties has died.
What a Barder event is not
- It is not simply changing your mind about a fair deal.
- It is not usually a change that could have been predicted when the order was made.
- It is not a change in the value of property or shares, however large. In Myerson v Myerson [2009] EWCA Civ 282 the Court of Appeal said the natural processes of price fluctuation in houses, shares or any other property, however dramatic, do not satisfy the test. Commentary says applications based on the 2008 financial crisis and the Covid downturn have failed on the same basis.
Why timing matters
People regularly say the biggest surprise is how quickly they needed to act. Delay can count against an application, so anyone who thinks a Barder event may have happened usually takes advice promptly.
Where to go next
- Look up the term in our glossary.
- Use Start Here to find your stage.
- Read about McKenzie Friends and how they may help.
Sources
- Barder v Barder (Caluori intervening) [1988] AC 20
- Myerson v Myerson [2009] EWCA Civ 282
- Hasan v Ul-Hasan (Deceased) and another (Supreme Court, 28 June 2023)
- Family Procedure Rules 2010, rule 9.9A and Practice Direction 9A
- Charles Hogan, 3PB Barristers, Not What I Ordered: Attacking Financial Remedy Orders (5 July 2026)
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