Judicial intervention in costs budgets: The importance of a significant development
In the recently handed down personal injury case of Bassey v Whittaker & Watford Insurance Company [2026] EWHC 2126 (KB), Cavanagh J held that costs budgets cannot be revised according to CPR 3.15A without there being a significant development, subject to any agreement between the parties.
This was a personal injury claim brought by the Claimant following serious injuries suffered as a result of a road traffic accident. The Claimant was a pedestrian who was struck down by the First Defendant Driver in a car. The injuries were so significant that the Claimant became a protected person who lacks capacity to conduct litigation. The First Defendant played no part in the appeal or proceedings. The Defendants accepted liability during a costs and case management hearing. The appeal was brough by the Second Defendant, against the decision of a District Judge.
Given the serious nature of the Claimant’s injuries, there were a number of directions, which included an order approving both parties’ costs budgets in preparation of a 10-day multi-track trial. On 27 November 2025 a further directions order was made amending previous directions. The order was titled “CONSENT ORDER”. Of that order, the District Judge directed the parties to file and serve Precedent Ts pursuant to CPR 3.15 “to take account of the increased costs associated with the amendments to the [previous] order [December 2024].”
Precedent Ts were exchanged and a costs management hearing followed in February 2026. Following the February 2025 hearing, the recital to the order stated:
“Upon the Court recording that the amendments to the Order of DJ Maddison dated 18th December 2024 were not a significant development within CPR 3.15A but does not prevent the costs being increased” [16]
The question before the Cavanagh J was “whether the court has the power to vary costs budgets if the parties do not agree to this course of action, in circumstances in which the court has found that there have been no significant developments” [51] However, Cavanagh J held that the direction pertaining to Precedent Ts was neutral. It may have been required where there was a decision already made as to varying the budgets, or it was required for a subsequent hearing where parties consider revising their budgets. [29]
In his analysis Cavanagh J considered Master Kaye’s judgment in Persimmon Homes Ltd v Osborne Clark LLP [2021] EWHC 831 (Ch) which considered this very issue. While this is a judgment from a Master of the High Court, and not binding on Cavanagh J, he “entirely agreed” with the conclusion set out by Master Kaye. [60]
Cavanagh J’s finding was “it is clear from the purpose, structure and language of CPR 3.15 and 3.15A that (at least absent agreement between the parties) the existence of significant developments since the costs budgets were finalised is a necessary precondition before costs budgets can be varied. The court does not have a general discretion to vary costs budgets even if there have been no significant developments.” [60]
In contrast, CPR 3.15(6) affords the Court some discretion to amend costs budgets where a timetable has been set or direction has been given for further review. In this matter, no such timetable was set, therefore the “significant development” condition was a pre-requisite that does not apply to agreements nor pre-agreed reviews.
Cavanagh J considered the test for “significant development” was as set out by Master Kaye, “The “significant developments” test is satisfied if the development or developments is or are something that was not and could not reasonably have been anticipated by the applicant for revision at the time of the previously approved budget.” [79]
Significant developments are fact sensitive, but in this matter, the Court considered that parties should be prepared for cases of such serious nature that further quantum statements or further expert reports may be needed. Additionally, parties should anticipate that the trial window may “slip” and there would be additional disclosure. [86] and [88]
Key takeaways:
- A direction for filing updated Precedent Ts alone is not sufficient to grant the Court discretion to interfere with costs budgets. Cavanagh J held this direction was neutral.
- CPR 3.15(6) may allow some room for the Court to review costs budgets where a timetable has been set out. In this case, there was no such timetable.
- Significant Development depends on the facts of each case but remains an objective test. The Court will consider the nature of the litigation, documentary evidence or information available to the parties when completing the budgets and the work that could reasonably have been anticipated.
- Foreseeability of additional work can defeat arguments of significant development. In a serious personal injury claim where quantum is the only remaining issue, parties can and should have anticipated further work associated with the claim. Further expert reports and further quantum advices are clearly foreseeable given the nature of the claim.
- Parties are still free to agree to revise their costs budgets. Cavanagh J made a clear distinction between an agreement revision of the budgets and judicial intervention.
- Only costs occasioned from the significant development are permitted under CPR 3.15A.