Penalty fees and complicated accounts will push 2.9 million current account customers to switch banks over the next 12 months.

Research by data collection company Defaqto and comparison service MoneyExpert revealed four million people paid penalty fees on current accounts in 2005.

Some 2.8 million do not understand how their account works leaving them liable to fees, which are making customers want to switch accounts.

Sean Gardner, chief executive at MoneyExpert.com, said: "Industry experts have long argued that current account customers are unwilling to move banks as they believe the switch will be too much hassle.

"However this could be the year that customers finally start to wake up to the benefits of changing account and realise that a bank account doesn't have to be for life."

Banks and building societies are battling to make it worthwhile for consumers to switch and recent efforts include Nationwide upping their interest rate to 4.25 per cent, Coventry Building Society paying 5.1 per cent and Alliance & Leicester paying five per cent.