The Financial Ombudsman Service is to publish business-specific complaint data every six months for every firm that has at least 30 new and 30 closed cases during the period.
The watchdog says data will include the numbers of new cases and the percentage of closed cases where there has been a change of outcome in favour of the consumer.
Data will be broken down into five groups, including banking, home finance, general insurance and pure protection, decumulation, life and pensions and investments.
The FOS says it will identify any larger groups that businesses belong to as well as major trading names used.
The ombudsman rebuffs industry arguments that this could result in businesses paying unjustified complaints to avoid a referral and that publication of the data could undermine consumer confidence in the financial services sector.
It says: “Financial businesses will be encouraged to deal with complaints properly in the first place and if they are confident that they have treated the complaint fairly, they will stand by their decision.”
The first set of data is due to be published in September.
Philip J Milton and Company managing director Philip Milton says publishing the data will be detrimental to networks and firms with a big market share.
He says: “If a firm has lots of advisers and customers, they will obviously have more complaints than a sole trader but that does not mean they are offering a worse service to clients.
“It is not the FOS’s job to publicise complaint data. They are there to handle complaints, share data with the FSA if they have concerns and then it is up to the regulator to take action if it feels a firm is acting inappropriately.”
Which? personal finance campaigner Vera Cottrell says the proposals should go “much further”. She says: “Having a threshold of 30 complaints before a firm is named means that smaller companies could continue to get away with murder and no one would know.”