How Santander's New CEO Will Lead TSB Integration

Santander has appointed Mahesh Aditya as the next CEO of Santander UK, with the transition taking effect on 1 March 2026. 

Mahesh, who currently serves as Group Chief Risk Officer (CRO), takes the CEO role at the bank following nearly 10 years in senior and executive posts across the Santander Group. 

His new responsibilities include overseeing the acquisition and integration of TSB Banking Group, due for completion in early 2026 subject to regulatory and shareholder approval.

Santander confirmed the agreement to acquire TSB on 1 July 2025 from Banco Sabadell, valuing the transaction at US$3.4bn. 

Chair of Santander, Tom Scholar, says of Mahesh’s appointment: “I am delighted to announce the appointment of Mahesh Aditya as our new CEO. 

“With wide industry experience and deep knowledge of the Santander Group he is ideally placed to lead Santander UK through the next phase of our transformation and oversee a successful acquisition and integration of TSB. This will be critical to our ambition to be the best bank for customers in the UK.”

Leading the integration of TSB

Mahesh takes over from outgoing Santander UK CEO Mike Regnier. 

His new leadership coincides with the integration of TSB into the Santander portfolio. 

This acquisition adds scale to the Group’s presence in the UK market, and the move aligns with ongoing transformation initiatives within the bank.

Speaking on the development, Mahesh says: “I am pleased to be joining Santander UK as its CEO at such an important time. The acquisition of TSB will both accelerate our transformation and add to the considerable inward investment Group has made in the UK since it entered the market in 2004.”

Mahesh continues: “It presents us with a real opportunity to execute the Group's strategy in the UK, in which the integration of TSB will play a crucial role. It will enhance our offer to customers, enable us to grow and become a more competitive business creating genuine value for our investors.”

Santander’s acquisition of TSB covers 100% of TSB Banking Group plc shares. 

TSB operates approximately 175 branches and customer-facing outlets, serving close to five million customers across personal and small business banking.

According to Santander, the combined entity is expected to become the third largest bank in the UK by personal current account balances and the fourth largest by mortgage lending. 

In total, Santander UK and TSB will serve nearly 28 million retail and business customers. 

Santander highlights benefits for TSB customers, including access to the wider Group’s international network and digital platforms.

The Group has prior experience with major UK acquisitions. Santander acquired Abbey in 2004, followed by Alliance & Leicester and the deposit business of Bradford & Bingley in 2008. 

Santander states that it intends to integrate technology infrastructure across the combined group to support a more streamlined digital banking model.

Ana Botín, Executive Chair of Banco Santander, says: “The acquisition of TSB represents a continuing strategic commitment to our customers in the UK, offering a compelling opportunity that is financially attractive to our shareholders and aligned with Santander’s long-term objectives. 

“It strengthens our franchise in a core market through the acquisition of a low-risk and complementary business that adds to our diversification.”

Executive leadership and transition

Mahesh brings over 30 years of experience in financial services. 

His previous roles include senior leadership positions at Citi, JPMorgan Chase & Co and Capital One. 

Since joining Santander in 2017, Mahesh has held executive positions including CEO of Santander Consumer US. He also serves on the Santander UK Board.

To support the leadership transition, Santander names Pedro Castro e Almeida as the new Group CRO. Pedro joined the Group in 1993 and is currently CEO of Santander Portugal, a role he has held since 2019. He also served as regional head for Europe from 2023 to 2025.

During his time at Santander Portugal, Pedro led the bank through structural transformation and enhanced operational efficiency. His experience in European operations forms part of the Group’s broader succession planning across key leadership roles.