The mutual says it has seen a 26% week-on-week rise in the number of account openings. Among those that switched online, the rise is 85%.

John Crossley, head, current accounts, Nationwide, says: "Customers are clearly unhappy with recent events and are opting to vote with their feet."

However, new Ipsos Mori research for the Logic Group, suggests that the Nationwide bonanza could be just a blip, with customer loyalty to banks surprisingly strong despite four years of negative headlines.

A poll of 2018 people - carried out in April and May, before the latest scandals - shows that two thirds of Brits feel loyal to their financial services provider, a higher percentage than for, among others, supermarkets, mobile network operators and department stores.

The findings are backed up by Payments Council figures, which show that only eight per cent of customers switched or attempted to switch their personal accounts over the five years to 2010.

Switching may become more popular next year when the Council launches a system designed to make the process easier for consumers and small businesses.

Antony Jones, CEO, The Logic Group, says: "The recent events, including those from last week, should become a lesson for British banks in how not to exploit and dishonour customer trust and loyalty."