Lord Ashcroft
Business services
Rank 2017

Ashcroft sat in the Lords as a Conservative until 2015, the year he co-wrote a controversial biography of David Cameron, claiming he had a personal "beef" with the then prime minister. He built his fortune via the ADT cleaning and security business, making £500m when it was taken over, with other sales adding £332m. Ashcroft chairs Impellam, the UK's second largest staffing business, which saw profits surge to £39.4m on £1.8bn sales in 2015-16. He and his family own just over half the London-based operation, a stake worth £200m. The 71-year-old life peer has a collection of more than 200 Victoria Crosses held at the Imperial War Museum's Lord Ashcroft Gallery.