The Royal Bank of Scotland Group has officially confirmed that Chairman Sir Philip Hampton will leave the company during 2015 after a "suitable successor is appointed".
Hampton will join the board of GlaxoSmithKline as a non-executive director from 1 January 2015 and will assume the role of chairman from 1 September 2015.
"It has been a privilege to serve as chairman of RBS since 2009," said Hampton.
"I am looking forward to working with my colleagues in the months ahead as we work to implement the bank's strategy and continue to improve the support we provide to our customers."
Hampton was appointed to the RBS board on 19 January 2009, and to the position of chairman on 3 February 2009, only one year after the lender received £45bn (€58m, $73m) in bailout cash.
Hampton has managed to avoid the axe over the years despite former chief executive Stephen Hester being ousted after five years at the bank, following a raft of market manipulation scandals and mis-selling issues under his watch.
Prior to RBS Hampton was the chairman of J Sainsbury, group finance director at Lloyds TSB Group, BT Group plc, BG Group, British Gas and British Steel, an executive director of Lazards and a non-executive director of RMC Group and Belgacom.
He is also a former chairman of UK Financial Investments Limited, which manages the UK government's shareholdings in banks.