Andrew Bailey, a director of the Bank of England who will soon become the City's top regulator, has said that free banking is dangerous and needs to be reformed by the government.
Bailey says that free banking both misleads customers about how they are really paying for banking services, and also means that banks themselves may not properly understand the costs of the products and services they supply.
This fuzziness about the costs of banking services means there is a greater risk that banks will mis-sell other products, to boost their profits - he says.
And the lack of clarity increases the propensity for banks to push products they regard as best for themselves, rather than being what customers want.
The man who will soon become the City's top regulator wants customers to be given a much better sense of what they are paying for, and how they are paying.
He says banks can't be trusted to deliver this information, because the first bank to do so might look the most expensive bank in town and could lose lots of business. And if all banks got together to change their pricing practices, that would look like collusion.
Mr Bailey - who describes himself as a dog with a bone on this issue - says government or regulators will have to intervene to force banks to tell us the true cost of their services.