Jim Brown is leaving his role as Ulster Bank boss to take on another position within the Royal Bank of Scotland (RBS) group.
He's taking on the role as chief executive of Williams & Glyn – part of the RBS group.
Jim Brown said: "I am pleased to have been appointed to the CEO role at what is an exciting time for the business.
“We are committed to establishing a strong and credible challenger bank in the UK market and I look forward to the challenges ahead."
RBS branches in England and Wales will become part of Williams & Glyn when it launches, by the end of 2016.
Jim Brown saw his overall pay package jump by 66% last year as the bank returned to profit for the first time since the financial crisis.
He came in to the bank to return it to profitability – something which it did last year.
The bank posted all-Ireland operating profits of more than £600m in 2014 - spurred on by additional cash clawed back from loan impairments.
An improving economy also led to greater retail and corporate business.
RBS is spinning off 314 of its some 2,000 branches into its Williams & Glyn brand to meet European Union rules on state aid.
It was last on the high street nearly 30 years ago.
John Maltby will step down from his current role as chief executive at Williams & Glyn to resume a role as advisor to an external investors’ consortium involved in the spin out.
The New Zealander will remain in Ireland while a successor is appointed.