Consumer groups have argued that this has resulted in bank accounts being paid for by people who make mistakes and go overdrawn, many of whom are the least well-off and the least well-informed customers.

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There are no schemes to try to overcharge on overdraft by reordering the accounting process, but rather a live person will usually call you to say that your account has been overdrawn, and how we can help.

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"As a result of our problems today, some of our customers have gone to our ATMs and they've been able to withdraw more funds than they had in their account and therefore they've overdrawn their account, " spokesman Bryan Fitzgerald told the Australian Broadcasting Corporation.

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Why do the High Street banks pay us a tenth of 1% on our money but charge us 15% or more when they lend it to us and twice that if we go overdrawn?

BBC

Although only a quarter of customers go overdrawn each year, most of these had also done so the previous year and were more likely to do so six times a year than just once.

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At the time, the banks were facing a deluge of claims, both directly and via the courts, from customers who were angry about the amount they had been charged when going overdrawn.

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