The data revealed that Nationwide gained the most customers, with 40,656 people transferring to the building society, while 8,883 moved away (net gain: 31,773).

TSB recorded the largest net loss of 16,142.

A TSB spokesperson said: “Customers do not solely need to use the switching service, they can open a new bank account with us via our branch network or online. 

“In reality, in the third quarter of 2018, approximately 22,000 customers opened a new bank account with us or switched their account to us.”

The mobile banks using the service witnessed a large proportion of people switching to their platforms as opposed to those moving away.

Some 5,588 new customers joined Monzo, compared with just 225 who moved away from the digital bank.

Elsewhere, Starling Bank gained 2,362 and lost only 246.

Anne Boden, CEO at Starling Bank CEO said: “It's great to see is the number of people embracing digital banks and the benefits they can offer in terms of speed and accessibility.

“In the last year, Starling has seen an increase of more than 600% in customers and we’re hoping to reach one million in 2019.”

Specialist bank Triodos had its data posted for the first time on the service and recorded a net gain of 284 customers.

Gareth Shaw, head of money at Which?, commented: “Our research has shown that fresh thinking and innovation from some of the challenger banks has shaken up the market and put them ahead of some of the biggest banking brands for customer satisfaction.

“After a turbulent year of IT meltdowns that caused inconvenience to millions of people, anyone feeling frustrated with their bank should consider switching as there has never been an easier time to move to a new provider.”