Sky News has learnt that Sue Fox, who became chief executive of M&S Bank in 2014, has resigned to run HSBC’s Channel Islands and Isle of Man operations.
Ms Fox’s departure, which is expected in January, leaves one of Britain’s most popular ‘white-labelled’ finance businesses looking for a new chief.
M&S Bank is owned by HSBC but is structured as an equal profit share between the two parties.
A long-term deal between them expires next year, and could lead to M&S remaining with HSBC or switching the licence to use its brand in the banking sector to another partner.
Insiders believe the relationship with HSBC is likely to continue beyond the current contract.
M&S Bank, which is based in Chester, has around 4m customers across products including credit cards, travel insurance and – since earlier this year – mortgages.
In a statement issued to Sky News, an M&S spokeswoman confirmed that Ms Fox would be leaving her current role saying she would “support with recruitment of her successor and ensure a smooth handover”.
Last year, M&S Bank generated income of just over £40m, down about 20% on the previous year as a result of new accounting standards triggering higher bad debt provisioning.
The lender, which has its own banking licence and board, has 29 branches in M&S stores across the UK.
Earlier this autumn, the retailer announced the appointment of Kirsty Ward as director of M&S Bank and services, encompassing the energy business it runs in conjunction with Octopus.
News of Ms Fox’s exit from the M&S Bank role comes just hours before the high street retailer unveils half-year results expected to underline the enormous pressure on its board to accelerate an improvement in its fortunes.
The historically strong food business is showing increasing signs of strain even as the clothing division, which has been performing poorly for years, exhibits hints of a potential revival.
M&S has said it will close 100 stores by 2022, shifting more of its focus from physical floorspace to improving its digital offering.
Steve Rowe, who took over as chief executive in 2016, has his board’s support despite speculation among investors that chairman Archie Norman could seek to appoint a new boss as soon as next year.
The retailer’s executive team has already been largely overhauled under Mr Rowe, with a further change imminent.
Dominic Fry, who has run M&S’s communications function throughout the tenure of Mr Rowe and his predecessor, Marc Bolland, is to leave next month.
He is to be replaced by Victoria Gould, an executive at the soft drinks maker Britvic.