Insurers are urging the Financial Ombudsman Service (FOS) to delay plans to name companies with the worst customer service, just as consumer complaints are expected to skyrocket to record levels.

In a drive to be more open, the ombudsman wants for the first time to name the companies involved in the tens of thousands of consumer disputes its hears.

But in a response to a consultation on how best to present this data, the Association of British Insurers is urging the ombudsman to halt its plans until a number of its concerns are addressed.

“No firm-specific complaints data should be published until both FOS and the industry are confident that the FOS is delivering consistent decisions and recording them accurately,” said the ABI. “Any data which is published must be fair, clear and not misleading.”

The ABI wants the FOS to hold off until the outcome of a Financial Services Authority consultation on similar proposals to publish company-specific data. It said: “Un- co-ordinated change could lead to customer confusion, duplication and additional costs for firms.”

The FOS proposes only naming companies that have had 30 new cases and 30 closed cases against them in six months. But insurers say a more reliable and helpful measure would be a percentage of closed cases, upheld by the FOS.

Consumer groups, which have long campaigned for “naming and shaming” companies that treat customers badly, say this threshold should be as low as three complaints, with the product involved and issue also published.

“The spotlight of publicity, and the attendant changes in what people buy, do more to improve standards in an industry than anything else,” said Which?, the consumer group.

The developments come as the FOS this week said it expected its workload to jump 44 per cent to 165,000 cases in the coming financial year, with most new complaints mortgage-related.

The British Bankers’ Association (BBA) said it was urging the FOS to give “proper consideration of what they intend to publish and why”.

“The information has to appear in its proper context – once it is in the public domain it can be peeled, washed and chopped and can result in unfair conclusions being published as fact,” said a spokesperson.

The ombudsman is considering responses to its consultation and expects to produce a feedback statement in the next few months.