Top 30 M&E contractors see turnover rise 7.9%

UK: The latest survey of the top 30 largest M&E contracting firms shows a collective turnover of nearly £6.8bn in 2025, up 7.9% on the previous year.

The annual report by the Building Engineering Services Association (BESA) insists that the mechanical & electrical contracting market has shown impressive resilience in the face of challenging economic conditions.

“We have been in a state of flux for some years now,” said Gokhan Hassan managing director of GHCS and GH Engage, which carried out the financial research for the Top 30 UK M&E Contractors report.

“Since recovering from Covid in 2022/23 the collective turnover figure has risen from £4.7bn to more than £6bn which coincides with the explosion of the mission critical sector.”

BESA points out that the top 30 list, which places Leeds-based NG Bailey at the top in 2025 with a turnover of £706.7m, is not exhaustive or definitive. It is based on data compiled from a mixture of accounts provided directly by contractors who responded to this survey and other public sources.

The report shows that data centres and the wider digital infrastructure market along with healthcare, defence, energy transition and the push for compliance with building safety legislation are feeding into market growth. However, the fall in residential work has held back parts of the industry and led to the collapse of some long-established firms.

Office construction and fit-out is providing a steady pipeline of work and new entrants into these markets are evidence of sector resilience. PFI ‘hand backs’ to the NHS estate are also creating a huge refurbishment and retrofit opportunity for the industry, according to BESA’s research.

“The future of the M&E sector is bright; the evolution of the Building Safety Act (BSA), intelligent buildings, resilient MEP infrastructure and environmental awareness will propel building services to contribute even further towards economic growth,” observed Gokhan Hassan.

Other significant factors emerge from the report such as the importance of investing in innovation and improving the efficiency of processes to keep up with the demands of clients in the digital, defence and healthcare markets. Many firms say they have moved on from the sector’s traditional “first past the post” approach to tenders and are improving efficiency in design and delivery.

BESA chief executive officer David Frise described it as an exciting time for the industry, “There is great demand out there for high-quality building engineering work and the challenge of turning opportunity into business success is also driving companies to be more innovative,” he said.

However, several of the firms featured in the report said that protecting margins and cash flow continued to be challenging due to persistent inflation, coupled with fixed-price contracts and project delays, which increased risks and harmed profitability.

As a result, M&E contractors report being more selective about the work they take on by focusing primarily on sectors offering more resilient, longer-term pipelines, such as mission-critical infrastructure and retrofit, and relationships with clients who engage them earlier in the design process.

Several also highlighted the importance of proposed legislation to outlaw retentions and crack down on unfair payment practices as critical to protecting cash flow and reducing the risk of insolvency.

The Top 30 UK M&E Contractors report is available for download from the BESA website.