Patterson, who served 14 years at the company, five of which as CEO, will stay at the company until BT has appointed his successor.
The move comes just weeks after Patterson announced a major restructuring plan which would see BT move out of its London HQ after 150 after three years and 13,000 employees, or around 13 per cent of BT's global workforce, axed over the next three years in a bid to cut costs amid tumbling revenues.
At the same time, Patterson was embroiled in fractious talks with Britain's telecoms regulator Ofcom about the fate of Openreach, which runs the national broadband network.
Mr Patterson expanded BT beyond its core business by investing in its TV arm and buying football broadcast rights.
BT shares plummeted after it was announced, and are now trading near a six-year low. The first and most important is the share price.
Former Fleetwood Mac guitarist Danny Kirwan dies
Kirwan was born in Brixton, South London, and his guitar skills started attracting attention at an early age. He remained active briefly, recording unsuccessful three solo albums for the British label DJM in 1975-79.
The restructuring plan announced last month was meant to cut costs, improve profits and release cash to invest in 5G.
Jan du Plessis, the chairman of BT, said: "The Board is fully supportive of the strategy recently set out by Gavin and his team".
Mr Patterson became managing director of BT's consumer division in 2004.
Patterson has been with the United Kingdom incumbent telco for 14 years, serving as a member of the Board for the last ten.
He managed to avoid a full break-up of the group by agreeing to legally separate Openreach, but he admitted he had been taken aback by the flak BT had received about its customer service and its networks during the bitter two-year battle.
"BT is a great business and, with the new management team I've recently put in place, is, I believe, very well positioned to thrive in the future", he said.