National Australia Bank (NAB) has warned its customers not to provide credit card details to people who ring up claiming to be from the bank.
An NAB spokesperson said that scammers have pretended to be calling from NAB, the Australian Taxation Office (ATO) or the Department of Fair Trading advising customers they have been overcharged on fees and are due a refund.
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Customers are then asked to provide their banking details so the refund can be transferred.
"A bank will never ask for your full credit card details over the phone, and NAB advises all of our customers to be aware of the practical steps they can take for their personal and business security," the spokesperson said in a statement.
"Customers who received a phone call of this type are advised to contact our Internet banking support team immediately on 1300 651 656."
NSW Fair Trading recently issued a warning that residents were receiving calls about refunds on bank fees.
Scammers told consumers they had obtained funds owing to them from a bank and that in order to receive the money, people needed to deposit money for administrative purposes.
The promised bank refunds ranged in size from $5000 to $9000.
NAB has been contacted for more information by Computerworld Australia.
Follow Hamish Barwick on Twitter: @HamishBarwick