Treble, current vice chairman, has previously served as chair of both Saffron’s remuneration and risk committees having joined Saffron’s board of directors in 2014.
He takes over from Geoffrey Dunn, who retires from Saffron after nine years on the board, including six as chairman.
Treble said: “Having already served on Saffron’s board for several years, I am delighted to be appointed as chairman.
“Geoff has been a well-respected and hands-on chairman who provided strong leadership and a relentless focus on the interests of our members.
“He has been a tremendous advocate for the Society, and I am looking forward to continuing this work.”
Colin Field, Saffron Building Society CEO, added: “Following a rigorous selection process, we are delighted to announce that the board has appointed Nick as chairman.
“We have every confidence that he will do an outstanding job in his new role.”
The Society also confirmed that David Rendell has been appointed to the board as a non-executive director. As part of his role, Rendell will be chairing the building society’s risk committee.