Sales of Payment Protection Insurance (PPI) are to be investigated by the Office of Fair Trading (OFT) over claims that insurers are not treating customers fairly.

The OFT is to examine whether consumers face difficulties in getting information they need about alternative suppliers, and if the information available can be understood easily.

The regulator will also assess the “wide degree of variation in pricing” in the sector, and the fact that providers “gross profit margins appear high”.

PPI is applied to a number of credit products including mortgages, loans and credit cards and protects a borrower’s ability to keep up their payments in case of accident, sickness or unemployment, usually for 12 months.

The OFT investigation follows a super-complaint from Citizens Advice (CitA), and the regulator will now conduct a market study to examine the problems with the insurance sales in more detail.