The move comes as current chief financial officer Andy Penn assumes the role of chief executive, a role that David Thodey has held for six years.

Mr Bray joined Telstra in 2009 as the telecommunication company's head of corporate strategy. He became head of mobiles in 2010 and assumed his current role in 2013.

At the end of the 2009 financial year, Telstra had 10.2 million mobile subscribers. Now it has 16.4 million mobile subscribers, while its nearest rival, Singtel's Optus, has 9.4 million.

"Warwick has decades of knowledge in and around telecommunications and technology and significant financial experience, proven by his business results in Telstra and other companies," Mr Penn said.

"We are pleased to have appointed Warwick from within our executive ranks, highlighting the depth of talent within the business. He is well regarded in the industry and has a proven track record in leading and significantly growing multibillion-dollar businesses."

Telstra's managing director consumer Karsten Wildberger will take on Mr Bray's current responsibilities until a replacement is found.

A new head of Telstra international, a role held previously by Mr Penn, is yet to be found.