A recent Court of Appeal decision provided important clarification on how legal costs were calculated when a Part 36 settlement offer was accepted late.

Background

The Claimant in Attersley v UK Insurance Ltd [2026] EWCA Civ 217 was injured in a road traffic accident in March 2018. Whilst the claim began under the Road Traffic Accident (RTA) Protocol, it exited the protocol and in February 2021, the Claimant issued Part 7 proceedings, valuing the claim up to £150,000 supported by several expert reports.

The Defendant admitted liability in March 2021 and made a Part 36 offer in the sum of £45,000. The Claimant did not accept this offer within the 21-day relevant period set by the rules. Consequently, the claim was allocated to the multi-track in January 2022, which typically allows lawyers to recover their costs based on what is considered reasonable rather than fixed amounts. The Part 36 offer was accepted in July 2022.

As the Claimant accepted the Part 36 offer outside the 21-day relevant period, and once the claim had been assigned to the multi-track, there was a dispute as to whether the costs could be recovered on a standard basis or were limited to fixed recoverable costs.

Outcome

The Court of Appeal considered the version of the civil procedure rules which applied at the time and held that the key date is when the 21-day period for accepting the Part 36 offer expires, rather than when the offer is eventually accepted, meaning that Claimants who accept an offer after the relevant period will generally be entitled to the amount of costs they would have received had they accepted the offer on the last day of the relevant period. As during that 21-day period the claim remained within the fixed costs regime, the Claimant was entitled to fixed costs which applied at that stage of the proceedings.

The court highlighted that the rules governing settlement offers are designed to encourage early settlement and clarity surrounding financial risk, therefore Defendants should be able to rely on the costs environment that existed when the offer’s relevant period expired. Allowing later events, such as the case being allocated to the multi-track, to change the cost consequences would create unnecessary uncertainty. The court outlined that:

“it is hard to see why a Claimant who [accepted the offer outside the relevant period]…should be in a better position than one who accepts the offer within time.”

Conclusion

The key point of this judgment is that if an offer is made and expires while the case is still within the fixed‑costs regime, the fixed‑costs rules apply to the consequences of accepting that offer, even if the case later evolves or moves outside the fixed‑costs regime.

Although this decision was made in the context of the pre-October 2023 fixed costs rules, it is expected that this is the same approach the Courts will apply under the new fixed‑costs rules introduced in October 2023. That is because those rules are also built around clear stages and predictable cost consequences.

Angela Nako is a Paralegal in the Costs and Litigation Funding Department at Clarion Solicitors. You can contact the team at civilandcommercialcosts@clarionsolicitors.com