More than a million current account switches were made last year, new data from the Current Account Switching Service - or CASS - shows.
Most switches were made between September and December, with 350,114 completed through the service.
End-user data, reported three months in arrears, showed that Nationwide gained the most customers at 41,450, between July and September.
The UK's biggest building society's head of product, Fred Powell, said: "Customers tell us they value great service, choice and convenience and that's what we're focused on delivering.
"We've also topped the CASS switching tables once again, with a sizeable gap between us and number two, and the really good news is that our switching offer of £175 is still running."
This was followed by Monzo, which gained 9,934 customers, and NatWest, which reeled in 8,731 new accounts.
At the bottom of the table was Santander, which lost more than 19,900 accounts.
CASS found the majority of switchers (72%) preferred their new account, and only 2% said it was worse.
Using online or mobile app banking was the top reason why consumers preferred their new accounts, followed by customer service, interest earned and spending benefits.