The poorest people in Scotland are being penalised by unfair overdraft charges, according to a report by Citizens Advice Scotland.
It has accused the banks of creating "a reverse Robin Hood effect".
It said the banks' poorest customers were subsidising the richest by paying a higher part of their income in fees.
One pensioner was charged £66 for going overdrawn by 60p. Citizens Advice has called on banks to show more fairness and discretion when charging fees.
Citizens Advice Scotland chief executive Susan McPhee said that despite talk about being more responsible, banks were still imposing heavy charges on vulnerable people.
She said people were struggling to get by in the recession and that banks should show more discretion in how they applied charges.
Ms McPhee said: "What is particularly disappointing is that the people who are worst hit by these charges are those who can least afford to pay them."
She said that the poorest were having to pay a higher proportion of their income than those who were better off.
"Indeed these charges mean that the poor are actually subsidising the rich, like a reverse Robin Hood effect."
Ms McPhee said banks often made the problem worse by offering to consolidate loans.
"If the banks themselves will not act fairly then the government should force them," she added.
"After all it's only a year since the public bailed out the banks and saved them from disaster.
"It's time the banks paid people back for that."