On 30 June 2026, a collective action was filed at the Competition Appeal Tribunal (CAT) that could become the most significant consumer litigation the UK property sector has ever seen. If you bought a new-build home in the last decade — or if you built and sold one — this case demands your attention.

What Has Happened?

A class action has been launched on behalf of over 700,000 people who purchased new-build homes in Great Britain between October 2015 and June 2026. The defendants are eight of the UK’s largest housebuilders: Barratt Redrow, Bellway, Berkeley Group, Bloor Homes, Persimmon, Taylor Wimpey, Vistry Group and its Countryside Partnerships division.

The allegation is serious: that these companies shared commercially sensitive pricing, incentive and sales data with one another, reducing competition and causing buyers to overpay for their homes. The total compensation sought sits between £2.2 billion and £4.5 billion — equivalent to between £3,100 and £6,200 per affected homeowner.

The claim follows a Competition and Markets Authority investigation that concluded in October 2025, when the housebuilders agreed to pay £100 million into affordable housing programmes and accepted binding commitments to stop sharing certain data. Crucially, no formal infringement finding was ever made — and that fact sits at the very heart of what makes this case so legally significant.

Why This Case Is Legally Groundbreaking

This is not simply a large claim. It breaks new ground in several important ways.

First, it tests whether a CMA settlement that stopped short of a formal infringement finding can still support the certification of an opt-out collective action before the CAT. That question has never been answered by a UK court. The outcome will set a precedent that shapes competition litigation for years to come.

Second, the scale of the opt-out mechanism means that affected homeowners are included automatically unless they actively choose otherwise. This places an enormous potential liability on the defendant housebuilders before a single piece of evidence has been tested at trial.

Third, the disclosure obligations alone will be significant. The seven defendant companies can expect requests covering years of pricing data, internal communications, sales incentive structures and buyer analytics — much of it already examined by the CMA.

Are You a Homeowner Who May Be Affected?

If you purchased a new-build property from any of the named developers between October 2015 and June 2026, you are potentially included in this claim automatically. You do not need to take any action to be covered — but you should take advice on your position, particularly if you are considering whether to opt out, or if you have related disputes with your developer around defects, warranties or contract terms that could interact with this claim.

Griffin Law has deep experience in property disputes and in advising individuals who find themselves caught up in large-scale litigation they did not initiate. We can help you understand what the claim means for you, what to expect as it progresses through the CAT certification process, and how to protect your interests at every stage.

Are You a Developer, Contractor or Construction Business?

The ripple effects of this claim will extend well beyond the eight named defendants. Subcontractors, suppliers, consultants and other parties with commercial relationships with the defendant housebuilders face real exposure — from disclosure requests and contractual disputes to reputational risk and regulatory scrutiny.

If your business sits anywhere in the supply chain of the UK’s major housebuilders, now is the time to review your contractual position, your insurance cover, and your litigation readiness. Griffin Law’s construction and commercial litigation teams work with businesses across the sector, advising on everything from contract enforcement and professional negligence to regulatory investigations and dispute resolution.

For the defendant housebuilders themselves, the immediate priorities are clear: litigation hold obligations, disclosure management, and a robust challenge to the CAT certification process. The case cannot proceed to full trial without a Collective Proceedings Order being granted — and that certification hearing represents the first, critical battleground.

The Bigger Picture for the Construction Sector

This claim arrives at a moment of intense scrutiny for the UK housebuilding industry. Regulatory pressure, planning reform, the Renters’ Rights Act, building safety obligations and now the largest competition class action in the sector’s history — the legal landscape for construction businesses has rarely been more complex or more consequential.

Whether you are defending a claim, pursuing one, or simply trying to understand what this seismic shift in the legal environment means for your business, Griffin Law is ready to help.

We act for both claimants and defendants. We know construction. And we know how to fight.

July 2026 | Griffin Law

Griffin Law is a dispute resolution firm comprising innovative, proactive, tenacious and commercially-minded lawyers. We pride ourselves on our close client relationships, which are uniquely enhanced by our transparent fee guarantee and a commitment to share the risks of litigation. For more details of our services please email justice@griffin.law or call 01732 52 59 23.

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