British companies established in 1981

British multinational telecommunications services company

British multinational enterprise accounting software company

British newspaper publisher

Petrofac Limited is a British international energy services company that designs, builds, manages and maintains oil, gas, refining, petrochemicals and renewable energy infrastructure, and trains the people who support them. It operates in a range of markets from design to decommissioning. It is registered in Jersey (number 81792), with its main corporate office on Jermyn Street, London. It has 7,950 employees across more than 30 offices globally. It was for a time in the FTSE 100 Index. In October 2025 the Petrofac holding company filed for administration.

sports-fashion retail company

Homebase was a British home improvement and garden centre retailer that operated across the United Kingdom and Ireland.

former British video game company acquired by Mirrorsoft

British publishing company

British dairy products company