Networks Openwork and Sesame saw complaints against them at the Financial Ombudsman Service (FOS) rise in the second half of last year, with Sesame receiving over 90% more claims.
New complaints against Sesame rose from 138 in the first six months of 2012 to 263 in the final half of the year, up 90.5%.
This included 26 complaints about mortgage and home finance, 26 complaints about general insurance, 69 complaints about payment protection insurance (PPI), 67 complaints about investments and 73 complaints about life and pensions and decumulation.
Openwork received 132 new complaints in the six months from 1 July to 31 December 2012, up from 100 in the first six months of last year, a 32% increase.
This breaks down as 1 complaint about banking and credit, 26 complaints about mortgage and home finance, 9 complaints about general insurance, 50 complaints about PPI, 24 complaints about investments, and 22 complaints about life and pensions and decumulation.
The number of complaints sent to the 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 followed by Barclays with 44,725 complaints, and Bank of Scotland with 39,375.
Complaints about 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).
