More than one million people closed a bank account in the last year, with some banks losing more than five per cent of their customers as people switched institutions or consolidated their accounts.According to a Roy Morgan Research report released yesterday, 46,000 Bankwest customers (representing 5.6 per cent of its customer base) closed their accounts during the 12 months to July.There were 43,000 closures at ING Direct, representing 5.2 per cent of its customer base.Among the Big Four banks, ANZ suffered the worst fallout, with 157,000 customers (representing four per cent of its customer base) closing their accounts.There were 56,000 closures at St George, representing 3.8 per cent of its customer base; 108,000 closures at Westpac (three per cent of its customers); 31,000 at Bendigo and Adelaide Bank (2.9 per cent of its customers); 192,000 at Commonwealth Bank (2.7 per cent of its customers); and 70,000 at National Australia Bank (2.3 per cent of its customers).Roy Morgan's industry communications director, Norman Morris, said: "Our research shows that the key reasons why people switched their main financial institution included high fees and charges, poor service and poor interest rates."