From 1769–85 he was an insurance clerk with the Royal Exchange Assurance Corporation.
It took its name from the location of its offices at the Royal Exchange, London.
As Lord Onslow he was a leading participant in an insurance business known as Onslow's Insurance or Onslow's Bubble, which secured incorporation under the Bubble Act as Royal Exchange Assurance Corporation.
Royal Navy | Royal Air Force | Canadian Broadcasting Corporation | Royal Dutch Shell | Australian Broadcasting Corporation | Royal Society | New York Stock Exchange | Royal Albert Hall | Royal Shakespeare Company | Royal Opera House | Oracle Corporation | Royal Victorian Order | Royal Engineers | Royal Australian Navy | Royal National Theatre | Royal Canadian Navy | Royal Canadian Air Force | International Finance Corporation | Chevron Corporation | Royal Court Theatre | Royal Marines | Royal Commission | London Stock Exchange | Royal Academy of Music | Anne, Princess Royal | Royal Philharmonic Orchestra | Theatre Royal, Drury Lane | Royal Flying Corps | Royal Canadian Mounted Police | Royal Australian Air Force |
Other business positions held by Dent included chairmanship of the Caledonian (Ceylon) Tea Estates and the Shanghai Electric Construction Company and directorships of the Chartered Bank of India, Australia and China, the London County and Westminster Bank and the Royal Exchange Assurance Corporation.
Broseley Estates Limited, also referred to as Broseley Homes, was formed by Danny Horrocks after an amalgamation of developers and was controlled for most of its history by the insurance company Royal Exchange.