Sesame says claims management companies are to blame for the number of complaints against the network going up by 87 per cent year-on-year.
Data from the Financial Conduct Authority, published yesterday, shows Sesame had a total of 1,978 complaints between July and December last year, compared to 1,060 in the same period in 2011.
Sesame upheld 15 per cent of its complaints in the second half of last year, down from a 24 per cent uphold rate in the second half of 2011.
A Sesame spokesman says the number of complaints represent a “tiny proportion” of the business written by members.
He says: “Whilst the overall number of cases has increased, the percentage being upheld has continued to reduce. Claims management companies are behind many of these complaints, with cases often referred to us regardless of their individual merits.
“Sesame takes its regulatory responsibilities very seriously. We fully investigate all complaints and we are satisfied the procedures we have in place ensures a consistent and fair approach to complaint handling and treating customers fairly.”