The first Eurotherm company, Eurotherm Controls, was formed in 1965 at Worthing, West Sussex, specifically to manufacture temperature controllers. Within five years, the entrepreneurial directors of the company had set up a number of loosely related but independent companies to develop and produce other advanced product lines. Chessell Ltd was created to manufacture data recorders, while Turnbull Control Systems (TCS) was formed to produce advanced process control systems, and Shackleton System Drives (SSD) to produce variable speed electronic drives. All four companies marketed their specialist offerings internationally, and in 1974 it was decided to create an international holding company, Eurotherm International, to bring management control together under one umbrella.

By 1978 the highly successful holding company was strong enough to “go public” and it became quoted on the London Stock Exchange in May of that year. By 1989, Eurotherm International controlled a significant network of subsidiaries and agents around the world, including the UK, USA, Switzerland, Germany, France, Hong Kong, Italy, Japan, Australia, Holland, Belgium, Scandinavia, Spain, Korea, India and Ireland. It was acquired by Siebe plc June 1998, later to become Invensys plc.

By the late 1990s, three key Eurotherm companies, Eurotherm Controls, Eurotherm Recorders (previously Chessell) and Eurotherm Process Automation (previously Turnbull Control Systems) amalgamated to form Eurotherm Limited, a corporate structure which is still in place today.

In 2009 Eurotherm, along with several other Invensys businesses (Foxboro, IMServ Europe Ltd, Skelta, Triconex and Wonderware), formed Invensys Operations Management, a global provider of automation and information technologies, systems, software solutions, services and consulting to global manufacturing and infrastructure industries.