Dunstone realised that mobile phones would eventually become ubiquitous and left NEC in 1989 to start his own business serving this larger market.

[4] Naming his company The Carphone Warehouse (CPW), emphasising a broad choice of products and low prices, Dunstone first began selling mobile phones out of his flat on Marylebone Road in 1989.

In December 2019, Dunstone purchased £10 million worth of shares in TalkTalk, meaning he now owns 29.5% of the company's stock.

[7] Dunstone employed the controversial ex-convict Ernest Saunders as a business consultant for Carphone Warehouse prior to its flotation.

[12] Dunstone has 3 A-levels, grades B,C & D.[3] He abandoned his business degree at Liverpool University after taking a gap-year with Torch Computers in Cambridge and then with NEC.

[13] He was made a Knight Bachelor in the 2012 Queen's Birthday Honours List 'for services to the mobile communications industry and to charity'.

[14] In the 2015 Queen's Birthday Honours List, he was appointed Commander of the Royal Victorian Order (CVO) for his work with The Prince's Trust.

[15] Dunstone established a charitable trust, which is the main sponsor of the Fulwood Academy school in Preston, Lancashire.