Founded in a basement in Leeds as Bailey-Billington (as we were first known) with an initial capital of £83. Our team of 12 carried out domestic electrical installations and relied on a borrowed handcart for transport. Our turnover in the first year was £5,000. One of our first projects involved installing wiring in a 12th-century manor house in Norfolk. This early success helped establish our reputation, and in 1922, Noel Grimshaw Bailey bought out his partner and formed the business as we know it today.

In the 1930s, we became a limited company and opened our first electrical goods shop in Leeds. The shop grew to become the largest distributor of Hoover vacuum cleaners in the area. We expanded regionally by opening an office in Manchester. In 1934, we launched our apprenticeship scheme, now award-winning, and recruited five apprentices to support our growing workload.

During the 1940s, we contributed to the country’s war efforts by supporting essential military projects. After the war, we shifted our focus to major industrial developments and expanded into the atomic energy sector, including work on the Windscale plutonium factory

In the 1950s, we continued to grow, with a major focus on the UK’s developing nuclear industry. We worked on the country’s first nuclear power station at Calder Hall in Cumbria and on the Blue Streak rocket programme. This work also led to opportunities overseas, with projects in the Middle East.

We moved into pipework installations, broadening our services beyond electrical work. We completed our first multi-storey office building at the Merrion Centre in Leeds. By the end of the decade, we had established our own engineering academy in Leeds, with a dedicated office and training school, the first facility of its kind in England for the electrical contracting industry.

This was a period of further expansion as we opened new offices in Dundee and Bristol and launched a consultancy business in Bradford. During this time, we completed a £75,000 electrical installation at a WM Morrison supermarket and a £1.1 million installation at Brighton Marina. In 1978 we welcomed our largest apprenticeship intake to date, with 144 apprentices joining the business.

We expanded again, upgrading our Denton Hall office to accommodate our growing range of training courses. We concluded the decade with the formation of NG Bailey Manufacturing, bringing together our switchgear, instrumentation and industrial process control teams.

We entered the heating, ventilation, and air conditioning market and launched Bailey Maintenance Services, which became the foundation for our Facilities Infrastructure Services. We also completed work at Sizewell B, which opened in 1995.

We achieved our first Investors in People Award and exceeded £600 million in turnover. We also formed Bailey Prefabrication and Bailey Teswaine, which later evolved into Offsite Manufacture (OSM) and IT Services.

Our acquisition of Freedom Group gave us a presence in the UK electricity distribution network market. We also secured our largest contract to date, worth more than £600 million, at Hinkley Point C, the UK’s first new nuclear power station in two decades.

We responded to the COVID-19 pandemic by helping deliver NHS Nightingale Hospitals in Harrogate, Manchester and Cardiff. In 2025, we moved into our new HQ at White Rose Park in Leeds. That same year, we recorded turnover of £662 million, the highest in our 104-year history. In 2026, we acquired Engineering Solutions Group (ESG), a specialist engineering group operating across the water, environmental and wider infrastructure sectors.