Starting on March 1, 2026, Aditya will replace Mike Regnier, who decided to step down from the role in October 2025.
Aditya joined Santander in 2017 and has held several executive roles, including group chief risk officer and CEO of Santander Consumer USA, as well as serving recently on the Santander UK board.
“From his new role, Aditya will oversee the integration of TSB, once the acquisition announced in July 2025 is completed,” said the parent firm.
Santander UK said: “Mahesh joins from Banco Santander, where he has been Group Chief Risk Officer since 2023 and prior to that spent six years at Santander in the US, as Chief Risk Officer, Santander US for two years, followed by CEO of Santander Consumer USA from 2019 to 2023.
“He has over 30 years’ financial services experience having held positions across a range of blue-chip brands including Citi, JPMorgan Chase & Co and Capital One.
“Mahesh was appointed to the Santander UK Boards (Santander UK Group Holdings plc and Santander UK plc) on 1 October 2025. “
Aditya wrote in a social media post: “I am very pleased to be taking the role of CEO of Santander UK at the start of March. Having been part of Santander Group for almost a decade I know just how important the success of the bank in the UK is to the Group.
“Santander Group’s investments in the UK represent the largest inward investment into UK banking and one of the largest inward investments in the UK economy overall. That commitment is remarkable.
“As part of this investment, the acquisition of TSB, subject to regulatory approval, will accelerate the transformation of Santander UK and support our goal to become the best bank for customers and investors.
“I already know what a quality team we have in the UK at every level and I know how hard everyone in the UK is working – but I am also very much looking forward to meeting and hearing from many new colleagues over the coming weeks.
“I would like to thank Mike Regnier who I will succeed and who has been enormously supportive in the process of preparing me for the role. Mike has been a first-class CEO and everyone at Santander wishes him success and happiness in what he chooses to do next.”