Banks that receive the most customer complaints could be named and shamed under proposals outlined yesterday by the Financial Services Authority (FSA).

In its first discussion paper on increased transparency in its own dealings with the market, the City watchdog said that it could potentially list the worst offenders in a league table of poor customer care. It would also take into account how long the banks and financial services companies took to resolve grievances and what sort of recompense was handed out.

About 18,500 companies in the second half of last year provided details of customer complaints to the regulator. But the FSA estimates that if it published complaints data, about 400 companies would account for roughly 99 per cent of all reported complaints.

The FSA is required by law to keep some information private but said it was also allowed to publish more details in other areas. The proposals also include naming more companies that the FSA has investigated as well as highlighting those that have done well.

“We believe that transparency is an important regulatory tool,” said Hector Sants, FSA chief executive. The FSA is inviting feedback on its proposals by August 29.

Separately, banks have been accused of denying millions of savers the chance to benefit from a rapid cash transfer service that was launched yesterday. Electronic payments between deposit accounts can now be dealt with within hours, rather than four days, but consumer groups have said that the banks are delaying the process because they can make up to £30 million a year by sitting on the cash.

Eddy Weatherill, of the Independent Banking Advisory Service, a consumer organisation, said: “By dragging their feet the banks can continue to profit. The launch is nothing but a publicity exercise.”

In theory, savers should be able to make payments of up to £10,000 by phone or online with funds leaving their account and arriving on the same day. From June 6 the service will be extended to standing orders, with a limit of £100,000.

However, only a fraction of payments will be quicker from day one. Initially, only eight out of 70 retail banks will allow customers to send payments using the service. Of the biggest high street banks, only Royal Bank of Scotland customers will be able to transfer £10,000 using the system immediately.

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