Could collusion among big housebuilders be blocking self-builders from the market?

The UK’s biggest housebuilders are under scrutiny as the Competition and Markets Authority investigates possible anti-competitive behaviour.

The probe, now extended until August 2025, is looking into whether firms shared sensitive information that may have delayed developments and affected prices of new homes.

While no formal conclusions have been reached, the inquiry raises concerns about how these practices could be affecting those looking to self-build and homebuyers.

What’s at stake in the investigation?

The investigation centres on allegations that seven major housebuilders may have coordinated by exchanging commercially sensitive information – such as future development timelines, pricing strategies and sales forecasts.

The firms under investigation include:

• Barratt Developments
• Bellway
• Berkeley Group
• Bloor Homes
• Persimmon
• Taylor Wimpey
• Vistry Group

According to the CMA, if confirmed, such information-sharing could amount to collusion, reducing competition in the housing sector.

Originally due to conclude by the end of 2024, the probe has been extended to August 2025, underlining the complexity and seriousness of the case.

While no formal accusations have been made, the investigation could result in significant consequences if wrongdoing is proven – including fines or future regulatory oversight.

The self-build squeeze across the UK

Self-builders may be facing an uphill battle in a market where a handful of companies control large amounts of developable land.

If large housebuilders are delaying projects or coordinating supply, land availability for smaller-scale building may shrink, prices may rise and competition for building plots can become untenable.

Experts have long noted that major developers often hold extensive land banks, sometimes delaying builds to manage supply and maintain profitability. This practice, sometimes referred to as "land banking," can make it difficult for self-builders to find plots in accessible or desirable locations. In rural and semi-rural areas – where self-build demand is growing – this squeeze is especially acute.

The concern is that potential collusion at the top of the market could have ripple effects all the way down to individuals trying to build their own homes, reducing not only opportunity but also innovation and architectural diversity in the UK’s housing stock.

The broader impact on buyers and the market

The possible coordination among big builders could also be limiting competition that would otherwise drive down house prices and speed up delivery of new homes.

With the cost of living still high and housing demand outstripping supply in many areas, reduced competition could mean fewer choices and higher prices for first-time buyers and growing families.

This could prompt renewed calls for government intervention to open the market to smaller players – including self-builders, housing associations and community-led housing projects.

In the long term, the CMA’s findings may push for a shake-up of how land is released and developed in the UK, and how power is distributed between volume builders and those seeking more individual routes onto the housing ladder.