The number of complaints sent to the Financial Ombudsman Service (FOS) doubled in the last six months compared to the previous half year period, with Lloyds topping the list of shame.
During the six-month period to 31 December 2012, the ombudsman service took on a record total of 283,251 new complaints - a 110% increase on the previous six months.
Out of these 95% of cases came from 197 financial businesses - out of more than 100,000 businesses covered by the ombudsman.
Lloyds was the most complained about with 45,727 complaints. It was follwed by Barclays with 44,725 complaints, and Bank of Scotland with 39,375.
Complaints about payment protection insurance (PPI) made up three quarters (74%) of the total complaints referred to the ombudsman during the second half of 2012 - with 211,885 new PPI complaints (compared to 85,562 in the previous period).
Five financial services groups accounted for 78% of all new PPI cases received between 1 July and 31 December 2012. In total, the ombudsman has received more than 600,000 complaints about PPI.
Across all individual businesses included in the data, the uphold rate for PPI complaints ranged from the ombudsman finding in the consumer's favour 97% of the time, to businesses where only 6% of complaints were upheld against them.
Natalie Ceeney, chief executive and chief ombudsman, said:"The number of PPI complaints has continued to increase at unprecedented levels and we are now regularly taking on around 2,000 new cases each day. Over the last year or so, we have geared up substantially to deal with these record complaint numbers and we are now resolving more cases each week than ever before.
"However, as the complaint levels show no sign of slowing, consumers are increasingly having to wait longer to get their complaints sorted - with many businesses still continuing to cause unnecessary delays.
"Where businesses have shown a real commitment to better customer service and diligent complaints handling - including actively engaging with the ombudsman - cases are resolved more quickly and easily, to the benefit of everyone."