PPI is a form of insurance that covers people in case they cannot pay loans as a result of illness or unemployment.
There are an estimated 20 million policies active in the UK, but critics claim PPI is often sold to people who do not need it, the price is excessive and policies are difficult to claim on.
Researchers from Which? contacted 41 loan providers for quotes and found that more than half the quotes received by telephone automatically included PPI, while quotes sourced over the internet revealed similar outcomes. Only one provider did not include PPI on their telephone quote, with a handful of others quoting for a loan including and excluding PPI.
Martyn Hocking from Which? said "by adding PPI to loan quotes automatically, people could be tricked into buying it regardless of whether they need it or not."
By including it with a quote people could see PPI as compulsory. "PPI is not always suitable, yet our research shows that lenders are still extremely keen to sell it to us," Mr Hocking said.
In February of this year the Office of Fair Trading formally referred the payment protection insurance industry to the
Competition Commission, following a period of public consultation.
John Fingleton, chief executive of the OFT said: 'Our examination of the evidence presented to date gives us reasonable grounds to suspect that there are features of this market which restrict competition to the detriment of consumers.