Poor customer service, poor advice, and mis-selling of financial products are the main reasons for complaints.
Marc Gander from the campaigning Consumer Action Group said "We're used to banks treating their customers shabbily; however these figures are quite extraordinary. You have to wonder where these billions of pounds of taxpayers' money are being spent, it's certainly not on complaints handling."
Peter Vicary-Smith, chief executive of the consumer organisation Which?, said: "Yet again, the big high street banks are failing to put customers first. The banking industry urgently needs to overhaul the way it treats its customers if it's going to rebuild its shattered reputation."
"Clearly a reform of the way bank staff are incentivised is needed; bonuses should be linked to treating customers fairly and the resolution of complaints, not to sales. At least, by getting rid of the lengthy two-stage complaints process, the FSA is ensuring that complaints will be dealt with more quickly from now on."
With some banking products more than 70 per cent of customers were found to have been given poor advice or service.
Craig Gedey, marketing manager at Debt Advisory Line said: "These reports cannot be good for consumer confidence in the UK banking system. At a time when bank fees and charges seem to be rife it is essential that people manage their finances well to avoid any penalties."
"Often people fall into arrears because of bank charges and struggling to repay these charges along with other debts and monthly bills can sometimes escalate into thousands of pounds worth of debt."
"At Debt Advisory Line we provide award winning debt management advice to help people manage their debts. Visit www.DebtAdvisoryLine.co.uk or call 0800 157 7254.
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Debt Advisory Line is the Debt Management Provider of the Year 2008 and 2009. Debt Advisory Line is a Debt Solution Company offering help and advice award winning "best Debt Management Plans", IVAs, Trust Deeds, Debt Relief Orders and Bankruptcy.