The appeal decision in Bassey v Whittaker & Watford Insurance Company Europe Ltd [2026] EWHC 2126 (KB) reinforces the restrictions on varying an approved costs budget. Where there is no significant development in a case, the court does not have a general discretion to vary costs budgets.
Costs budgets are intended to give parties and the court a degree of certainty about the costs of future stages of litigation. That certainty would be somewhat weakened if an approved budget could be revised whenever a party believed its costs had become greater than originally budgeted.
In this judgment, Mr Justice Cavanagh provides an important reminder of the limits on the Court’s power to vary an approved costs budget. Mr Justice Cavanagh emphasises the fact the Court has a discretion to vary an approved costs budget only once the requirements of CPR 3.15A are satisfied; and a “significant development” in the litigation is an essential prerequisite to obtaining any variation under CPR 3.15A.
It is, therefore, not sufficient to merely argue that costs have increased, that the litigation has become more expensive, or that the original budget has proved to be inadequate, as reasons to vary the budget. The Applicant must state genuine examples of significant developments in the litigation to justify a revision.
Background Facts
The appeal arose in the context of a personal injury claim brought by the Respondent who suffered serious injuries when he was struck by a car driven by the First Defendant. The Appellant is the Second Defendant, the First Defendant’s insurer. The Appellant had admitted liability and the proceedings were proceeding as to quantum.
The Respondent’s budget was approved by DJ Maddison at the Costs and Case Management Conference on 18 December 2024, at approximately £1.03m. The Appellant’s budget was approved at approximately £341,000. The case was complex, involving substantial medical and non-medical expert evidence and a projected 10-day Trial.
A further hearing took place on 27 November 2025, before DJ McLoughlin, where the Appellant made an application to vary the directions set by DJ Maddison on 18 December 2024. A directions order was made, which included at paragraph 3 a direction that the parties file and serve Precedent Ts to take account of the increased costs associated with the amendments made to the 18 December 2024 Order.
The Respondent sought a further £238,350 and a Costs Management Hearing was listed for 6 February 2026. The preamble to the Order dated 6 February 2026 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”.
The issues in the appeal
The main question on appeal was whether, having found that the varied directions were not a significant development under CPR 3.15A, the District Judge had power to vary the approved cost budget.
The High Court rejected the Respondent’s argument that the November 2025 order amounted to an agreement that the budgets could be revised, or that there had been significant developments. The reference in the November 2025 order to preparing Precedent Ts was so these would be ready if it was later decided there were significant developments and budgets should be revised. The High Court also found that the District Judge had decided that there had been no significant developments, as recorded in the preamble.
Mr Justice Cavanagh referred to Master Kaye’s Judgment in Persimmon Homes Limited v Osborne Clark LLP [2021] EWHC 831 (Ch), on the matter of whether significant developments are a necessary pre-condition to the variation of a cost budget.
Mr Justice Cavanagh agreed with the conclusions set out by Master Kaye in Persimmon Homes, that it was clear from the purpose, structure and language of CPR 3.15 and 3.15A, that the existence of significant developments since the cost’s budgets were approved were a necessary precondition before a costs budget could be varied. This confirmed that the Court does not have a general discretion to vary costs budgets if there have been no significant developments. The court left open the position whether there was power to vary costs budgets in the absence of significant developments if the parties were agreed, as this did not arise on the facts; Mr Justice Cavanagh declared this point should be decided in a case in which it arises.
The meaning of ‘significant developments’ is not defined in the CPR. Mr Justice Cavanagh further relied on the words of Master Kaye in Persimmon, stating that “an order for variation cannot be made in order to remedy a budget in respect of developments which could or should have been covered at an earlier approval or variation.” He then went on to state that just because some estimates and assumptions change, does not mean that those developments are considered to be significant developments. It would not be in the interests of justice or the overriding objective if there was scope to continuously revise costs budgets if there are frequent developments in the litigation.
Conclusion
The appeal was allowed because the District Judge had no power to order variation of the costs budgets when he had found there had been no significant developments since the costs budgets had been finalised, and he had not erred in this finding
A development under CPR 3.15A will not be considered to be ‘significant’ merely because it leads to additional work and an approved costs budget is not automatically capable of being varied simply because the costs have increased. Mr Justice Cavanagh made clear that “it would not be in the interests of justice or the overriding objective if there was scope for constant tinkering with budgets if there are developments in the litigation”. There must be a genuine and significant change in the litigation which warrants revision. Filing a Precedent T does not itself establish entitlement to variation of the cost budgets.
For practitioners, the safest approach is to monitor budgets continuously, identify significant developments as they occur, record their impact on future work and make any necessary application promptly.
Ujjaini Mistry is a Paralegal in the Costs and Litigation Funding Department at Clarion Solicitors. You can contact the team at civilandcommercialcosts@clarionsolicitors.com.