JBX v Frimley: When Losing the Main Issue Does Not Mean Losing Your Costs

A clinical negligence claimant lost the principal issue at an eight-day trial but still recovered 85% of his costs. JBX v Frimley shows why failed issues, costs causation and Part 36 have to be analysed separately.

JBX v Frimley Health NHS Foundation Trust (Costs) [2026] EWHC 2525 (KB) is a dedicated High Court costs judgment following a substantial clinical negligence damages award. Including interim payments of £950,000 and allowing for CRU payments, the claimant’s damages were assessed at £4,341,302.86, as well as substantial periodical payments. That made him the successful party overall.

But the Trust had won what the judge called “the principal battle”: whether the claimant’s future care needs should be met through the domiciliary care arrangement advanced on his behalf. The Trust argued that should have major costs consequences. Andrew Kinnier KC, sitting as a Deputy Judge of the High Court, disagreed, and ordered the Trust to pay 85% of the claimant’s costs on the standard basis, subject to detailed assessment if not agreed.

The short answer

Does losing the main issue at trial mean a successful clinical negligence claimant loses the costs of that issue? No. The court has a broad discretion under CPR 44.2. Success or failure on individual issues is relevant, but there is no automatic rule that a successful party’s costs must be cut every time it loses an argument.

In JBX the claimant lost the central future care and accommodation issue, which had occupied most of the trial. But the court also found that:

• the claimant remained the successful party overall, and won the lost years claim;
• it had not been unreasonable to take the domiciliary care case to trial;
• considerable expert-related costs had been incurred before the Trust’s case on care crystallised;
• quantum on the other heads of loss stayed in dispute until shortly before the hearing;
• the Trust had not protected itself with a Part 36 offer; and
• the conduct complaints on both sides had no meaningful costs consequences.

The result was a 15% reduction, not the far more severe order the Trust sought.

What happened in JBX v Frimley?

The trial turned on the claimant’s future care and accommodation. He advanced what the judgment calls “option 1”, a domiciliary care arrangement. The Trust opposed it: its pleaded case was that residential, not domiciliary, care best met his complex needs. The Trust won that issue.

It was not a side issue. The judge recorded that the greater part of the eight-day trial, the factual and expert evidence and the submissions were concerned with it. By contrast, the lost years claim, which the claimant won, took only around half a day.

That left the court with the question this article is about: how should costs be dealt with where the claimant has won the case overall but lost the main battle fought at trial?

What costs order did each side want?

The claimant argued for the ordinary result under CPR 44.2: the Trust should pay his costs on the standard basis, subject to detailed assessment if not agreed.

The Trust proposed something very different: 75% of the claimant’s costs up to 17 February 2026, and no order as to costs after that. That would have left the claimant recovering nothing at all for the period after 17 February 2026, including the trial itself.

The date was not arbitrary. On 17 February 2026, after the Trust served its Counter Schedule and expert evidence, the claimant’s solicitors wrote that settlement could not be achieved on the basis of the claimant remaining in residential accommodation. The Trust’s case was that the letter left it no alternative but to go to trial. As explained below, the judge did not accept that.

CPR 44.2: who was the successful party?

The starting point was CPR 44.2. The general rule is that the unsuccessful party pays the successful party’s costs, but the court may make a different order. In deciding what order to make it considers all the circumstances, including conduct, whether a party has succeeded on part of its case even if it has not been wholly successful, and any admissible offer to settle that is not a Part 36 offer.

The judge identified the claimant as the successful party because he had secured a substantial award of damages. That remained the starting point even though the Trust had won the future care issue.

Losing an issue, and losing the principal issue

The judgment applied the familiar authorities, including Fox v Foundation Piling Ltd [2011] EWCA Civ 790 and Welsh v Walsall Healthcare NHS Trust. Litigation rarely involves one party winning every argument, least of all complex personal injury and clinical negligence litigation. A claimant may succeed overall while failing on individual allegations, recovering less than claimed or having expert evidence rejected. The mere fact that the successful party did not win every issue does not, of itself, justify an issue-based order.

But the judge also accepted that the position may be different where the claimant has lost the principal argument at trial on which the outcome substantially turned. That is what happened here, and it is why there was a reduction at all. The real question was how large it should be.

Costs causation: when did the issue crystallise?

One of the most useful parts of JBX is its focus on the link between the failed issue and the money actually spent.

The judge found that the claimant’s future care and accommodation was not unambiguously contentious until 13 February 2026, when the Trust, after some delay, served its Counter Schedule and expert evidence. By then considerable expert-related costs would already have been incurred, except the costs of the without prejudice discussions, preparing the joint statements and attendance at trial. (He rejected the claimant’s argument that the Trust’s case was not clear until later still: the Counter Schedule had pleaded it.)

Other issues also stayed live. Quantum on the other heads of loss was not agreed until shortly before the hearing, and the lost years claim was disputed to the end. Having found that it was reasonable to take the care case to trial, the judge concluded that the need for lay and expert evidence could not have been reduced more than it was.

That gives a valuable distinction for detailed assessment: a failed issue and the costs caused by that failed issue are not the same thing. A paying party seeking a reduction should be able to say what expenditure would actually have been avoided had the point not been pursued.

The 17 February letter was not a costs watershed

The Trust made much of the 17 February 2026 letter. The judge was not persuaded that it had any costs consequences at all. The parties still attended the joint settlement meeting on 17 March 2026, and after a pause of four weeks they went on making offers and discussing quantum and the reverse indemnity. The letter was no impediment to negotiation, and the evidence was inconsistent with the submission that it left the Trust no alternative but to go to trial.

The lesson is general. A firm statement of one party’s position does not, by itself, make the later costs the other side’s responsibility. If a party says a letter changed the costs picture, it has to show that it actually did.

Was it unreasonable to pursue domiciliary care?

No, and that finding was central. The claimant’s case on option 1 was founded on one witness’s evidence, but it did not rest on that alone: domiciliary care was also supported by a neurologist, in the neurologists’ joint statement and in oral evidence, and by another doctor’s report. In those circumstances the judge held that it could not fairly be said that it was unreasonable to run option 1 to trial, or that it should have been conceded before trial.

Reasonableness and success are different questions. A properly supported position can be reasonably advanced and still fail. The court preferring the other side’s case does not retrospectively make the work done on the unsuccessful one unreasonable. That matters when answering Points of Dispute that amount to “you lost this issue, so all the associated costs go”.

The Part 36 problem for the NHS Trust

Neither party made a Part 36 offer. Offers were exchanged between counsel from 20 April to 5 May 2026, in the fortnight before the trial started on 6 May 2026. They included the Trust’s offer of 29 April 2026 (a £4 million lump sum, gross of interim payments, CRU and interest, plus periodical payments) and the claimant’s offer of 5 May 2026 (a £6.5 million lump sum, gross of CRU, plus periodical payments).

The judge accepted that the Trust’s offer was closer to the final result than the claimant’s. But, citing Jackson LJ’s observation in Fox, he said Part 36 provides the mechanism by which a defendant should protect its position, and the Trust had taken no steps to do so. Its offers were also made less than a fortnight before trial, by which time the bulk of the costs had been incurred. In that context the judge found “some force” in the claimant’s submission that the Trust was seeking the advantages of Part 36 without ever having made a Part 36 offer.

A sensible offer is not the same as Part 36 protection

This is the strongest settlement-strategy lesson in JBX. An ordinary without prejudice save as to costs offer can still be relevant under CPR 44.2, but it does not recreate the prescribed consequences of Part 36.

For defendants, the safest way to obtain structured costs protection is a compliant Part 36 offer, made early enough to influence how the case is run. For claimants, a defendant’s ordinary offer should still be taken seriously, but it is not the same as an expired Part 36 offer. Timing matters too: an offer made after most of the expert and trial preparation costs have been spent is commercially different from one made in time to stop them being incurred.

Conduct arguments need costs consequences

Both sides criticised each other’s conduct. The Trust relied on matters including the claimant’s disclosure exercise and aspects of the evidence. The judge gave these points little weight because none had any meaningful costs consequences. Even the deficiencies in the claimant’s disclosure had no real effect on increasing costs, or none that the Trust had satisfactorily identified.

The practical rule: do not merely identify bad conduct, explain what it cost. A conduct argument is far stronger if it can point to duplicated work, additional expert evidence, an unnecessary application, extra disclosure, an adjournment, further counsel preparation or another identifiable tranche of expenditure. Without that link it may remain background, and carry little weight in the final costs exercise.

Why was the reduction 15%?

There was no formula. As the courts have long recognised, the exercise requires a broad-brush approach. On one side, the claimant was the successful party, won the lost years claim, reasonably pursued the care case, had incurred much of the expert cost before the issue crystallised, and faced a defendant with no Part 36 offer and conduct points with no costs consequences. On the other, he lost the principal battle on future care and accommodation, which had taken up most of the trial.

Balancing those matters, the judge ordered the Trust to pay 85% of the claimant’s costs on the standard basis, to be subject to detailed assessment if not agreed. There was no application for a payment on account, which the claimant’s counsel anticipated could be resolved by agreement.

Why JBX matters in clinical negligence costs

Clinical negligence claims often involve several reasonable possibilities being investigated at significant expense. Future care alone can need evidence from care and accommodation experts, occupational therapists, neurologists, neuropsychologists, case managers and others. The court may ultimately prefer one care model over another. That does not mean investigating the rejected model was unreasonable, or that every cost associated with it should disappear from the bill.

The better question is: was it reasonable to investigate and pursue the issue when the work was done, and what additional costs did pursuing it actually cause?

JBX in Points of Dispute and Replies

JBX will be useful wherever a paying party challenges costs associated with an unsuccessful issue, typically by contending that expert, counsel or solicitor costs should be disallowed because the claimant failed on that part of the case. The Reply should address:

• Reasonableness: was the issue reasonably pursued on the evidence available at the time?
• Timing: when did the opposing position crystallise?
• Evidence: what expert or factual material supported the position?
• Causation: which costs would genuinely have been avoided if the issue had not been pursued?
• Overlap: would much of the work have been needed anyway?
• Settlement: did the paying party make an effective Part 36 offer?

That is much stronger than simply saying the claimant won overall. Our guide to Points of Dispute in clinical negligence detailed assessment covers the wider drafting approach.

JBX and the bill of costs

The same reasoning should shape the bill. Where a claimant has failed on a significant issue, the narrative should not pretend the issue does not exist; it should explain the litigation properly. That may mean identifying when the issue first became contentious, the evidence supporting the claimant’s position, the overlap with work needed regardless of the outcome, the chronology of the expert evidence, the defendant’s changing position and the settlement history. A clear narrative starts answering an issue-based challenge before the Points of Dispute arrive. Our guide to clinical negligence bills of costs and Precedent S explains how the electronic bill should be structured against the litigation.

JBX and Part 36 strategy

Part 36 is costs protection. If a defendant believes the claimant’s care model is excessive, that damages are overstated, that a particular issue will fail or that the claim should settle at a particular figure, a properly constructed Part 36 offer can change the eventual costs position. An ordinary offer made shortly before trial may still be relevant, but the court will not necessarily reproduce the protection that Part 36 would have given. What a Part 36 offer actually delivers also depends on whether it is accepted late or beaten at trial; see our guide to Part 36 late acceptance and the CPR 36.17 uplift.

What JBX does, and does not, establish

JBX does not establish that a successful claimant can lose a major issue without consequence: the claimant’s costs were reduced by 15%. Nor is 85% a benchmark for clinical negligence cases. CPR 44.2 gives the court a broad discretion and every case turns on its facts.

What JBX demonstrates is the method. The court did not simply identify the issue, identify who lost it and deduct its estimated cost. It looked at the litigation as a whole: overall success, reasonableness, timing, causation, settlement behaviour and conduct. Compare JXX v Archibald [2026] EWHC 2404 (SCCO), where the claimants and MROs were still the successful parties on the MRO costs despite an approximately 40% reduction to the fees. In both cases, who won is a different question from how much was lost.

Three practical lessons follow for claimant firms:

1. Losing an issue is not the same as incurring unreasonable costs. Ask whether the issue was reasonably pursued when the work was done.
2. Focus on causation. If the paying party wants a substantial reduction, ask what costs would actually have disappeared had the failed issue been abandoned.
3. Build the settlement chronology. A Part 36 offer, an ordinary offer and an offer made on the eve of trial are not interchangeable; their timing and status can change the costs order.

How DMD Costs can help

DMD Costs provides clinical negligence costs drafting and recovery support for claimant solicitor firms: Precedent H budgets and assumptions, bills of costs and Precedent S, expert fee recovery, N260 statements of costs, Points of Dispute, Replies, Part 36 costs analysis, negotiation and preparation for detailed assessment.

Clinical negligence costs often involve exactly the problems seen in JBX: several expert disciplines, changing litigation positions, significant care evidence, disputed quantum and substantial costs incurred before the final issues become clear. The bill should explain that history, not hide it. Send us a live file for a fixed-fee quote. JBX is also listed in our costs case law index, under partial success and issue-based costs orders.

Case details

Source: the approved judgment on The National Archives. Figures, dates and quotations are taken from the judgment.