Barclays Bank was the most complained about financial institution, racking up 23,703 complaints in a year, according to data from the Financial Ombudsman.
The vast majority of those complaints (19,522) were payment protection insurance related, with banking and credit complaints coming in second place with 3,208.
Of the PPI complaints, 93% were resolved in favour of the consumer, compared to an average of 71% across all financial companies, with 40% of resolved banking and credit complaints favouring the customer, compared to an industry average of 42%.
Lloyds Bank totalled 12,235 complaints, 9,493 of which were PPI-based. Almost all (98%) of them were resolved in favour of the consumer.
HSBC registered 7,164 complaints and Santander totalled 5,072. NatWest had 3,679, with RBS just behind with 3,053.
Credit card specialist MBNA also scored a high number of complaints, with 9,187 registered, 6,724 of which were about PPI. It resolved 97% of those in favour of the customer.
And building society Nationwide had 4,553 complaints lodged against it, 3,892 of them about PPI. Just 18% were resolved in the customer's favour however, compared to the 71% average.
The data, published on 11 September on the ombudsman's website, covers consumer complaints handled by the ombudsman service between 1 January and 30 June 2012.
During this six-month period, the ombudsman service received a total of 135,170 new complaints – a 27% increase on the previous period.
And 91% of the total number of cases came from 169 financial businesses, a relatively small number out of more than 100,000 businesses covered by the ombudsman.
Five banking groups had more than 8,000 complaints each referred to the ombudsman service, together accounting for 80,235 cases – almost 60% of all new complaints in this six-month period.
Commenting on the complaint statistics, Natalie Ceeney, chief executive and chief ombudsman, said in a statement: "The volume of PPI complaints doubled in the first half of 2012 – and has continued to increase since then with up to 1,500 new cases now arriving each day.
"We’ve also seen an increasing shift towards consumers doing it themselves rather than using a claims manager – with up to half of all new complaints now coming directly from consumers without paid-for representation, compared to less than 20% a year ago.
"This means our consumer front-line is busier than ever – taking over 3,000 calls on PPI a day and bringing much needed clarity to confused and bewildered consumers."
The Financial Ombudsman Service provides a platform for consumers to complain if they feel they've been mistreated by a financial institution.
The entirely independent body is tasked by parliament to investigate individual complaints, free of charge. Where the consumer has lost out, the Ombudsman can order the company to recompense them.
Individuals are free to take their case to court if they do not agree with the Ombudsman's decision.