High Court says there should not be “constant tinkering” with budgets
A district judge was wrong to hold that he had the power to vary an approved costs budget after finding there had not been a significant development within the meaning of CPR 3.15A, the High Court has ruled.
Mr Justice Cavanagh said that budgeting was “necessarily broad brush, and so the fact that some estimates and assumptions change as a result of future developments does not mean that those developments are significant developments”.
He continued: “It would not be in the interests of justice or the overriding objective if there was scope for constant tinkering with costs budgets if there are developments in the litigation.
“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.”
Bassey v Whittaker & Anr [2026] EWHC 2126 (KB) is a serious personal injury claim where liability was conceded and judgment entered at a case and costs management hearing in December 2024.
District Judge Maddison set directions for the quantum phase and approved the claimant’s incurred and estimated costs at just over £1m, almost half of what he had sought. The judge formally recorded that the incurred costs in the Precedent H were disproportionate. The defendant insurer’s budget of £341,382 was agreed.
At a hearing in November 2025, District Judge McLoughlin, who had taken over the case, varied the directions and, while formally stating that these did not constitute significant developments, ordered the parties to file and serve Precedent Ts to take account of the increased costs they would generate.
As a result, the claimant sought an extra £238,350.
The defendant appealed and Cavanagh J decided that the judge had erred. He cited with approval the 2021 ruling of Master Kaye in Persimmon Homes, which was the first detailed judicial consideration of rule 3.15A.
Cavanagh J said: “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. I reject [counsel’s] argument that such a general discretion is to be found in CPR 3.15(3). It is clear from the structure of CPR 3 that the power for the court to amend costs budgets must be found in CPR 3.15A, and so the preconditions of that rule must be met.”
He then considered whether the judge had been wrong to find no significant developments and decided it was “well within the generous ambit within which a reasonable disagreement is possible”.
He continued: “It was perfectly reasonable for the district judge to take the view that the developments were ones which could have been anticipated at the time that the costs budgets were finalised and therefore were not ‘significant’…
“It is almost always a possibility, in a case concerning assessment of damages for personal injury, that further expert reports and further quantum statements might be required. The possibility that there might be changes to the respondent’s condition as a result of new therapy or rehabilitation was an obvious possibility at the time of the costs budgeting exercise…
“What matters is that the district judge was entitled to find that the extra work by the medical experts was known or reasonably anticipated at the time that the budgets were finalised in December 2024, and so the further work by the medical experts did not amount to significant developments.”
Michael Lemmy (instructed by Keoghs) for the appellant. Simon Plault (instructed by McGrath Solicitors, part of GT Stewart Solicitors) for the respondent.