During the six-month period, the ombudsman service took on 327,035 new complaints – an increase of 15% on the previous six months. More than 95% of the cases came from 195 financial businesses – out of more than 100,000 businesses the ombudsman covers.

Complaints about payment protection insurance (PPI) made up more than eight out of ten (86%) of the total complaints referred to the ombudsman during the first half of 2013 – with 266,228 new PPI complaints compared to 211,885 in the last six months of 2012. Five financial services groups accounted for 78% of all new PPI cases.

Lloyds once again received the most complaints, a total of 129,293 in the period, up 38%.

For complaints about financial products other than PPI, the total number of complaints referred to the ombudsman reduced by 15% from 71,366 to 60,807 during the first six months of the year. This involved a decrease of 22% in banking complaints and 3% in insurance cases.

Across all individual businesses included in the data, the uphold rate – where the ombudsman found in the consumer’s favour – ranged from 2% to 98%.

Natalie Ceeney, chief executive and chief ombudsman, said: “During the first six months of this year we sorted out a record number of complaints for people – making real progress in tackling the customer-service fallout from the mis-selling of PPI, widely accepted as the largest financial mis-selling scandal.

“Disappointingly we are still seeing cases where businesses are not following our long-standing approach to PPI, resulting in long waits and unnecessary delays for consumers.

“But, more positively, we are seeing encouraging signs from some major businesses that are starting to recognise the value of getting things right for their customers – with an increased focus on sorting out problems and concerns as quickly as possible.”