Santander plans to close nearly one in five of its bank branches in the UK, putting more than 1,200 jobs at risk.

The Spanish-owned bank, which has one of the largest high street networks in Britain, will shut 140 branches, leaving 614 after the closures, which will be completed by the end of the year. Santander said it it expects to find new jobs for around a third of the 1,270 employees whose jobs are at risk.

The British banking industry is undergoing rapid change as more and more customers bank online through websites and mobile apps, reducing the number of visitors to branches on the high street.

Santander said branch transaction numbers have plunged by 23% over the past three years, while transactions via digital channels almost doubled over the same period. Other competitors among the British high street banks have also announced thousands of job cuts in the past year, with Royal Bank of Scotland gradually closing hundreds of branches.

Lloyds, Britain’s biggest high street lender, in November announced thousands of redundancies as it restructured its operations and launched a major digital recruitment drive. The takeover of Virgin Money by CYBG will result in 1,500 job losses.

Susan Allen, Santander’s head of retail and business banking, said: “The way our customers are choosing to bank with us has changed dramatically in recent years, with more and more customers using online and mobile channels.

As a result, we have had to take some very difficult decisions over our less-visited branches and those where we have other branches in close proximity.” Allen said branches still have a “vital role” in its plans and the bank expects its network to “remain stable for the foreseeable future”. Santander will spend £55m on refurbishing 100 remaining branches over the next two years.

By Jasper Jolly