The complexity of multi-party proceedings means that the costs incurred by each of the parties can be significant. One of the tools available to the court to control litigation costs is costs budgeting. In many cases, the value of a group action is likely to exceed the £10 million threshold for the application of the English court's automatic costs budgeting regime. However, costs budgeting will also apply where the claim form does not state that the claims are valued in excess of £10 million, and the court retains a general discretion to order costs management at any time. Costs management orders have thus been made in respect of a number of group actions, including White & Ors v Uber London Ltd & Ors (2025), where the court noted that costs budgeting would give the claimants visibility of their exposure in respect of the defendant's costs at an early stage of the case in circumstances where a preliminary issue trial had been ordered.
Equally, one of the key benefits of a group action is the efficiency that comes from determining common issues in a single set of proceedings. However, inevitably not all the work on a case will relate to every claim, and so multi-party proceedings can also involve complex questions around costs allocation.
In the context of a GLO, specific rules govern costs recovery, distinguishing between individual costs (costs incurred in relation to an individual claim on the group register) and common costs (costs incurred in relation to the GLO issues, individual costs incurred in a claim while it is proceeding as a test claim, and costs incurred by the lead legal representative in administering the group). In the Pan NOx Litigation (2025), the court noted that common costs claimed by non-lead firms "should be extremely limited", since their core work of looking after clients should be claimed in individual costs. Although there have been some suggestions that hourly rates in respect of common costs work might be higher than rates for individual cases, that suggestion was rejected in Hutson (Deceased) & Ors v Tata Steel UK Ltd (2025). The general rule is that all the members of the group will have several liability for an equal proportion of the common costs, together with individual liability for costs on their own claim. Where common costs have been incurred before a claim is entered on the group register, the court may order that claimant to be liable for a proportion of those costs.
By contrast, in a representative action, generally speaking only the representative will be liable for costs (although in practice any costs liability is likely to be covered by third-party funders and ATE insurance). It is, in theory, possible for the court to make a third-party costs order against a represented party but such orders are unusual.
Where multiple claims are brought together, the general position is that each party is liable jointly with each other for the whole of the reasonable costs of their common claim or defence, but only severally for the individual costs of their claim (see, for example, Baroness Lawrence of Clarendon OBE & Ors v Associated Newspapers Limited (2025)). However, in Re Ingenious Litigation (2020), which concerned claims by investors in various film finance partnerships, the court suggested that liability for adverse costs should be apportioned on the basis of their cash investment, such that the claimants shared risks proportionately to the possible rewards.