The Timetable Decides More Than the Arguments
Detailed assessment in clinical negligence runs on a sequence of fixed periods, and more recovery is lost to those periods than to any single argument about an item in the bill.
- Three months to commence detailed assessment proceedings, running from the judgment or order, the notice of discontinuance, or acceptance of an offer to settle (CPR 47.7).
- 21 days for the paying party to serve Points of Dispute after service of the notice of commencement (CPR 47.9(2)).
- 21 days for an optional Reply, running from service of the Points of Dispute (CPR 47.13).
- Three months from the expiry of the period for commencing detailed assessment proceedings to file a request for a detailed assessment hearing (CPR 47.14).
Two of those cut against the paying party. A party who serves Points of Dispute late may not be heard further in the detailed assessment proceedings without the permission of the court, and where no Points of Dispute are served within the period the receiving party may request a default costs certificate under CPR 47.11. On a clinical negligence bill that is a substantial remedy, and it is worth diarising the expiry date rather than waiting to see what arrives.
The paying party also has an obligation that is easy to overlook: PD 47 para 8.3 requires an open letter accompanying the Points of Dispute stating what sum, if any, is offered in settlement of the total costs claimed. Where that letter is missing, or offers nothing, it is worth saying so early.
Where the Budget Bites First
Most clinical negligence claims of any size are costs-managed, and that changes what detailed assessment is actually about. On a standard basis assessment CPR 3.18 requires the court to have regard to the last approved or agreed budget and not to depart from it without good reason.
The practical consequence is that the budgeted phases are largely settled before the Points of Dispute are drafted. What is left is incurred costs, which the budget does not protect in the same way, and the question of whether work has been placed in the phase it belongs to. That is where the substance of a clinical negligence challenge now sits, and it is why the budget and the bill have to be read against each other before any Reply is written. Our guide to clinical negligence costs budgets and the CCMC deals with how those phases are approved in the first place.
What Paying Parties Actually Challenge
Clinical negligence bills attract a recognisable set of objections. They are predictable, which means they can be drafted against rather than argued about afterwards.
1. Incurred costs
Pre-budget work is the first target, because it falls outside the protection of the approved budget. Investigation, records review and early expert work often sit here on a clinical file, and they need to be justified on their own terms.
2. Expert fees
Clinical negligence is expert-heavy, frequently across several disciplines, and expert fees are the largest disbursement in most bills. Expect challenges to the number of experts, the rate, the time spent on records, conference attendance and the cost of joint statements.
3. Medical reporting organisation charges
Where reports are obtained through an MRO, the charge is now treated as a disbursement rather than outsourced profit costs, and the mark-up is the point in issue. We deal with that separately in our note on JXX v Archibald and the 25% MRO mark-up.
4. Medical records costs
Records in clinical claims are voluminous, and the cost of obtaining, paginating and reviewing them is regularly disputed. The bill should show what was obtained, from whom and why, rather than presenting a single unexplained figure.
5. The breach and causation split
Where a claim succeeds on breach but the causation case narrows, paying parties argue that work directed at abandoned allegations is irrecoverable. Time recording that distinguishes breach from causation makes that argument answerable.
6. Seniority and delegation
Clinical negligence properly requires senior involvement, but not on every task. Expect the paying party to identify routine work carried out at a senior grade, and to say the file was under-delegated.
7. Hourly rates
Rates are challenged in almost every clinical bill, usually alongside grade rather than instead of it. The 2026 Guideline Hourly Rates are the starting point, but a claim above them has to be justified on the facts of the file, not asserted.
8. Counsel’s fees
Brief fees, conference fees and advice on quantum are all open to challenge, particularly where leading and junior counsel were both instructed.
9. Phase and task allocation
Where the bill is electronic, work placed in the wrong phase invites the argument that a phase has been exceeded when it has not. How the bill is built matters here, and we cover it in our guide to Precedent S and the electronic bill.
Replies That Comply With the Rules
A Reply is optional, but where one is served PD 47 para 12.1 limits it to points of principle and concessions only. It must not contain general denials, specific denials or standard form responses.
That rules out the line-by-line Reply that answers every item in turn. A compliant Reply identifies the points of principle that decide groups of items, concedes what is properly conceded, and leaves the rest to the assessment. Conceding early is not a weakness: it narrows the hearing and it is visible when the costs of assessment are decided.
Provisional or Oral Assessment
Provisional assessment applies where the costs claimed do not exceed £75,000 (PD 47 para 14.1). Many clinical negligence bills exceed that and proceed to an oral detailed assessment hearing, but lower-value clinical claims do fall within it.
Where it applies, CPR 47.15(5) caps the costs of the provisional assessment at £1,500 together with any VAT and court fees. That cap does not cover the cost of drafting the bill. A party who is dissatisfied with the provisional assessment has 21 days to request an oral hearing (CPR 47.15(7)), and there are cost consequences for doing improving on the outcome.
Offers and the Costs of Assessment
The receiving party is generally entitled to the costs of the detailed assessment proceedings (CPR 47.20), but that is a starting point rather than a guarantee, and Part 36 applies to detailed assessment proceedings with modifications.
The Part 36 consequences themselves are also worth getting right on the substantive claim, because they decide the basis on which the bill is drawn. In particular, late acceptance of a Part 36 offer does not trigger the CPR 36.17 uplift — a distinction that changes what can properly be claimed in the bill.
On a clinical negligence bill the offers chronology is worth building deliberately. A well-pitched offer made early, and beaten at assessment, changes the costs of the assessment itself, and the open offer the paying party is required to make under PD 47 para 8.3 is a useful marker of where they actually are.
A Practical Checklist
- Diarise the three-month period for commencing under CPR 47.7.
- Diarise the expiry of the 21-day Points of Dispute period, and consider CPR 47.11.
- Check the open offer letter required by PD 47 para 8.3 has been provided.
- Read the bill against the last approved budget before drafting anything.
- Separate incurred from budgeted costs, and be ready to justify the incurred side.
- Evidence the expert spend: who, why, how many disciplines, and what each produced.
- Show the breach and causation split in the time recording, not in argument.
- Keep the Reply to points of principle and concessions (PD 47 para 12.1).
- Check whether the bill falls under or over £75,000 for provisional assessment.
- Build the offers chronology early, and keep it open to inspection.
How DMD Costs Can Help
We prepare and negotiate clinical negligence costs for claimant solicitor firms: bills of costs and Precedent S electronic bills, Replies to Points of Dispute, expert and MRO fee challenges, and negotiation through to settlement or assessment. Every clinical file is subject to senior technical review.
If Points of Dispute have landed and the 21 days are running, send us the file and we will review the papers and confirm a fixed fee before any work begins.