Jan du Plessis, the chairman of BT, thanked Patterson for his contribution over the last 14 years but said the company needed a change in leadership.
He said: “The board is fully supportive of the strategy recently set out by Gavin and his team. The broader reaction to our recent results announcement has, though, demonstrated to Gavin and me that there is a need for a change of leadership to deliver this strategy.”
Investors welcomed the news, with shares rising 2.5% to 208p, making BT the top riser on the FTSE 100 and adding £400m to value of the firm.
The news comes after Patterson revealed a new restructuring plan for BT which included moving HQ away from the city and cutting 13,000 jobs.
Patterson was paid £2.3m last year, including a £1.3m bonus and a 1.5% rise in his basic salary.
Patterson commented, “It’s been an honour to lead BT since 2013 and serve as a member of the board for the last 10 years. Throughout that time I’ve been immensely proud of what we’ve achieved; in particular the transformation of the business in recent years, with the launch of BT Sport, the purchase and integration of EE and the agreement to create greater independence for Openreach.
“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.”
Prospect national secretary Philippa Childs said, "Gavin Patterson's announcement, about his departure later this year, leaves a void creating uncertainty for thousands of BT workers who are waiting to find out more details about recently announced restructuring plans.