United Kingdom

The right to bring a class action in England and Wales has developed through various procedural mechanisms that are not modelled on the regime of any other country. The representative action procedure (now Civil Procedure Rule (CPR) 19.8) dates back to the days of the Court of Chancery in the 19th century, before the enactment of the Supreme Court of Judicature Act 1873. Its most recent form was added to the CPR in May 2000 and permits a party to sue or be sued as the representative of a class of individuals, provided that one or more of the persons in that class has the “same interest” as the representative.

Those same amendments to the CPR in May 2000 also introduced Group Litigation Orders (GLOs) to allow the court to manage claims brought by a large number of claimants whose claims “share common issues of fact or law”. The introduction of GLOs was designed to achieve the following objectives:

• Allow access to justice, particularly in claims where the individual loss suffered is so small that proceeding with an individual action is uneconomic.
• Provide effective methods of resolving cases where the number of claimants and nature of issues mean cases cannot be managed properly through normal procedures.
• Achieve a balance between the rights of claimants and defendants.

The class action regime in Scotland has also been developing gradually over several decades, many of which mirrored similar reforms being considered in England and Wales. Most recently, the Civil Litigation (Expenses and Group Proceedings) (Scotland) Act 2018 received Royal Assent on 5 June 2018, with the Scottish Civil Justice Council’s working group publishing specific procedural rules which came in force in July 2020. Equally, there are various mechanisms available to bring a class action in Northern Ireland under the Rules of the Court of Judicature, including representative actions, procedural rules for joining together and/or consolidating claims.

In 2009, following a recommendation from the Civil Justice Council to introduce a more effective means of increasing access to justice, the UK Government announced its intention to pursue a “sector-based” approach to specialist opt-out collective actions regimes. Competition law was the first sector in which a bespoke UK-wide collective action procedure was introduced, by way of the Consumer Rights Act 2015, enabling claims to be brought on an opt-out basis in the Competition Appeal Tribunal (CAT).

This chapter will focus predominantly on the position in England and Wales.

The litigation landscape has changed dramatically with the rise of class actions. More than 60 collective proceedings are currently before the CAT. As of 1 March 2026, 125 GLOs have been granted by the High Court. The Scottish and Northern Ireland class actions mechanisms remain in their infancy, with 12 group proceedings given permission in Scotland since 2020.

The reasons for the significant growth in class actions include:

• The significant growth in third-party funding of litigation coupled with a specialist group of claimant law firms.
• Increasing scrutiny of corporate behaviour.
• New legal procedures such as the collective proceedings regime in the CAT.
• Rapid technological change and regulation giving rise to more stringent standards.
• The restriction of extra-territorial reach of U.S. courts for securities claims, which has driven claimants to bring claims in the English courts, particularly in relation to London-listed issuers.

Topical areas include but are not limited to Environmental, Social and Governance (ESG) and sustainability claims, data breach litigation, competition law infringements, product liability and consumer protection claims.

England and Wales has two parallel court systems in which group claims can be pursued: the High Court of Justice (which oversees general commercial litigation matters and has varied procedural tools) and the UK CAT (which only hears competition claims and has a bespoke collective actions regime). There are broadly five procedures available to manage class actions:

• Bespoke case management directions/test cases.
• Multiple claimants on a single claim form.
• Representative actions.
• GLOs
• Collective Proceedings Orders (CPOs) (in the CAT).

The latter three are most commonly used in practice and will be considered further below.

As noted in Section 1.2, above, separate procedures will apply in Scotland and Northern Ireland. CPOs in the CAT are applicable in these jurisdictions also.

Claims in the CAT must involve a breach of competition law, including but not limited to an abuse of a dominant position pursuant to the Chapter II Prohibition (found in section 18 of the Competition Act 1998) or anticompetitive agreements pursuant to Chapter I Prohibition (found in section 2 of the Competition Act 1998), respectively.

Non-competition class actions cover a broader spectrum, including but not limited to:

• Product liability claims for defective products.
• Breach of consumer protection legislation.
• Environmental claims involving breach of directors’ duties.
• Environmental regulations.
• Securities group claims involving breach of sections 90 or 90A of the Financial Services and Markets Act (FSMA) 2000.

There is no set definition for “class actions” in the UK; however, it can be broadly defined as legal proceedings where multiple claimants with claims sharing common characteristics seek a remedy against the same defendant or defendants, also known as “collective proceedings” or “group litigation”.

An important distinction exists between opt-out and opt-in class actions. Opt-out class actions are claims brought on behalf of a defined group without identifying all claimants or obtaining their authorisation; anyone falling within the group is included unless they specifically opt out. Opt-in class actions are claims brought only by those who decide to participate and specifically authorise the claim to be brought on their behalf.

In England and Wales, representative actions and GLOs are the two main procedural mechanisms, with day-to-day procedural management left to the court’s discretion.

Northern Ireland has broadly similar procedures which permit, amongst other mechanisms, representative actions by a party as representative of others with the “same interest” under the Rules of the Court of Judicature (Northern Ireland) but it does not have the equivalent to the formal GLO mechanism such as that seen in England and Wales. In Scotland, the Civil Litigation (Expenses and Group Proceedings) (Scotland) Act 2018 introduced a framework for group proceedings in 2020. Group proceedings in Scotland can be commenced in circumstances where there is a group of claimants with claims that raise issues of fact and law which are “the same as, or similar or related to, each other”.

In the CAT, there exists a bespoke regime imposed by statute and subject to the CAT Rules 2015. The existence of a defined “certification” process in the CAT comprises the most significant procedural difference from the High Court, providing clear “authorisation” and “eligibility” criteria against which a proposed collective action will be assessed for the purposes of granting a CPO.

The principal sources of funding, which can be used individually or in combination are:

• Conditional or contingent fee agreements (typically “no win, no fee” arrangements).
• After-the-Event (ATE) insurance providing cover for potential liability for adverse costs and disbursements if unsuccessful.
• Third-party funding, where a funder finances some or all of the legal costs in return for an agreed return from proceeds recovered.

In each jurisdiction, these arrangements are subject to rules and limitations. In Northern Ireland, a legislative framework for third-party litigation funding has been implemented by the Access to Justice (Northern Ireland) Order 2003. 

The usual rule that the loser pays the other side’s costs applies equally to class actions; its retention was seen as important in preventing the development of a U.S. style class action culture. In the CAT, costs can be awarded to or against the class representative, but not other represented persons unless specific exceptions apply. In a GLO, costs are split into “individual costs” and “common costs”.

The Supreme Court decision in R (on the Application of PACCAR Inc. and Others) v. Competition Appeal Tribunal and others [2023] UKSC 28 (PACCAR) held that litigation funding agreements providing for a return based on a percentage of damages recovered amounted to a damages-based agreement (DBA) and was therefore unenforceable. Litigation funders and litigants have since renegotiated their funding agreements to adopt compliant structures. However, there may be further changes to this position (see Section 4.1, below).

In England and Wales, test cases are unlikely to lead to swift resolution. Complex case management means that proceedings often take many years. As the Scottish mechanism is still in its infancy and the fact that several cases to date have settled, timeframes cannot be easily determined.

Most collective proceedings in the CAT take several years to resolve.

In most cases, UK class actions are brought by individuals or entities who themselves have a cause of action. However, the rules vary depending on the procedural mechanism and jurisdiction.

In England and Wales, a party may sue as representative of a class provided that one or more persons in that class has the “same interest” as the representative. GLOs operate differently. The granting of a GLO is at the court’s discretion rather than by right, and the court may establish a GLO of its own volition. The court may refuse an application if it is not satisfied that there will be a sufficient number of claimants to warrant the use of a GLO. In Scottish group proceedings, subject to certain conditions, the representative does not need to be a member of the affected group. This means that trade or consumer organisations may pursue claims on a group’s behalf.

In the CAT, a CPO will only be granted where it is “just and reasonable” for the prospective class representative to act on behalf of the class members. A prospective class representative is not required to be a claimant, although nothing prevents class members from taking up that position provided it is just and reasonable for them to do so.

In England and Wales and Northern Ireland, representative actions can theoretically proceed on an opt-out basis. However, in the former jurisdiction, permission is required to enforce a judgment or order by or against anyone who is not a party to the action. There is no limit to the number of eligible claimants that may join a representative action, nor is there any requirement for members of the represented class to be joined as parties to the action, or to be identified individually. GLOs operate on an opt-in basis. There is no requirement for all claims subject to a GLO to have been issued when the GLO application is made. There is no maximum number of claims needed for a GLO, although the Court of Appeal has made clear that “far more than two claimants are necessary”. A similar stance is adopted in Scotland.

When the CAT makes a CPO, it considers whether to allow the claim to proceed on an opt-in or opt-out basis, exercising wide discretion having regard to all relevant matters including the strength of claims and whether it would be practicable to proceed on an opt-in basis.

The UK courts and CAT have wide-reaching powers in both granting class actions and broad discretion in managing the same across all procedural mechanisms.

Disclosure and privilege may differ in each jurisdiction.

In England and Wales, disclosure is governed by Part 31 of the CPR (with PD57AD applying to cases in the Business and Property Courts), which requires standard disclosure of relevant documents, subject to privilege protections. Scotland does not have a general discovery procedure, although parties must produce any documents upon which their pleadings are based.

In the CAT, disclosure is not automatic but is ordered at the Tribunal’s discretion under rules 60 to 65 of the Competition Appeal Tribunal Rules 2015, with specific provisions for collective proceedings in rule 89, which permits disclosure between parties, class representatives, and class members as the Tribunal sees fit. Both recognise privilege as a key limitation on disclosure, protecting categories such as legal professional privilege from production, and the CAT has issued practice directions (including Practice Direction 1/2024) to manage confidential and sensitive information, ensuring disclosure remains proportionate, just, and cost-effective without creating procedural inefficiencies.

In principle, several heads of damage may be recoverable, subject to the principles applicable to the availability of each in the relevant jurisdiction. The law in Scotland is similar to that in England and Wales. The manner in which damages are quantified depends on the nature of the claim. 

The availability of aggregate damages in the CAT is a critical point of difference with the High Court regime, allowing proceedings to progress without establishing individual loss for each class member. Damages can be assessed on a “broad axe” basis (using estimations and assumptions) and awarded to the class as a whole at an aggregate level. The Supreme Court in Mastercard Incorporated and others v. Walter Hugh Merricks CBE [2020] UKSC 51 noted that the CAT is therefore probably uniquely qualified to surmount the difficulties of quantifying damages in such claims.

Class actions by their nature involve numerous parties, giving rise to particular settlement challenges including authority to settle, confidentiality, costs and how proceeds should be distributed. Alternative dispute resolution is available for all types of group actions, including mediation or informal without-prejudice roundtable meetings between class representatives and defendants.

Class action in England and Wales can generally be settled without juridical approval, subject to certain exceptions. In Scottish group proceedings, specific settlement rules require the representative party to “consult with” group members on the terms of any proposed settlement

Collective settlements in the CAT are governed by a specific statutory and procedural regime giving the CAT power to review and approve proposed settlements. The class representative and defendants must apply jointly for a collective settlement approval order, which the CAT will make if satisfied the terms are just and reasonable. Where an opt-out CPO has been made, the order will bind all UK class members who have not opted out and all non-UK class members who have not opted in. Where an opt-in CPO has been made, the class representative may not settle proceedings before the expiry of the opt-in period.

For GLOs, as the claims retain their individual character, any damages awarded at the end of the litigation will go only to those who actively made claims. In CAT proceedings, the damages are paid to the representative or another person the Tribunal considers fit. However, there has been significant debate over whether the collective proceedings regime is truly delivering benefits to class members.

Any judgment or order made by the High Court in representative actions is binding on all persons represented in the claim. However, court permission is required to enforce a judgment or order by or against anyone who is not a party to the action. In respect of GLOs, any judgment or order is binding on the parties to all other claims that are on the group register at the time the judgment is given, or the order is made unless the court orders otherwise. Judgments in test cases are used to decide certain key issues which inform how the rest of the class are dealt with, even if the judgment in the test case will not bind the parties to the other claims.

In August 2025, the UK Government called for evidence aimed at assessing the performance of the opt‑out collective actions regime in competition law over the past decade. It remains to be seen whether changes to the existing regime will be proposed by the UK Government. There have been calls to expand the CAT opt-out regime beyond competition law, but it is uncertain whether these efforts will succeed.

If the EU Representative Actions Directive (2020/1828) direction of travel is replicated in England and Wales, a further rise in product liability litigation can be expected. Similarly, if minimum damage thresholds are reduced as in the revised EU Product Liability Directive (2024/2853), the size of product liability claims could change dramatically.

In June 2025, the Civil Justice Council (CJC) published its report and recommendations on third-party funding in England and Wales considering access to justice, funding effectiveness and regulatory options. The main recommendation was to reverse the Supreme Court’s decision in PACCAR. On 17 December 2025, the UK Government announced that it “intends to take action to mitigate the impact of the 2023 Supreme Court judgment in PACCAR and implement proportionate regulation of third-party litigation funding agreements (LFAs)”. As part of this, the UK Government will firstly “legislate to clarify that LFAs are not DBAs, with prospective effect” and then “will introduce proportionate regulation of LFAs”. Once these two changes have been implemented, the UK Government will consider the CJC’s wider litigation funding recommendations in detail and announce any further changes in due course.