Of the 340,899 complaints the Financial Ombudsmen Service (FOS) received in its 2015/2016 financial year, 56% were related to payment protection insurance (PPI).

81.5% of PPI complaints were made for consumers by claims management companies, compared to just 14.5% of complaints made by consumers themselves. Outside of PPI and packaged bank accounts, 82% of complaints were made by consumers themselves.

Caroline Wayman, chief Ombudsman said: "In March 2016 we received our one-and-a-half millionth complaint about payment protection insurance (PPI) – accounting for half of all the complaints we’ve received since we were set up. These volumes of complaints – and the rate at which they’re still arriving each week – reflect the scale of the challenge that remains, two years after the peak of PPI, of fully restoring trust in financial services."

In November, the Financial Conduct Authority (FCA) launched a consultation about whether to place a time limit for consumer to claim back mis-sold PPI.

Of the remaining complaints, just 9% were related to consumer-credit products and services, such as hire purchase and debt collecting.

In total, the FOS received 3,072 complaints about hire purchase, up 72% year-on-year. Point-of-sale loan complaints grew 31% over the period to 2,071. Debt collection complaints fell 16% to 707 over the year, while credit broking complaints fell 54% to 563. Hiring, leasing and renting complaints increased 53%, to 508.

The largest bulk of consumer credit complaints were related to payday loans, which increased 178% to 3,216.
GAP insurance, which the FCA imposed significant changes for in 2015, was involved in 2% less complaints than the prior year.

The FOS warned that a significant proportion of the complaints it received about banking and credit involved people experiencing financial difficulties.

It said: "In our experience of resolving these complaints, we’ve found that people are often embarrassed that they’re struggling with their financial commitments – or worried about the consequences of admitting it. Unfortunately, this means some people who contact us have put off asking for help – and in the meantime, their difficulties have continued to escalate."

It reminded firms that when someone tells them they’re struggling, the business has an obligation to respond constructively. This could mean a number of things, the ombudsmen said, including agreeing to a repayment holiday or signposting people to free help with managing debt.

Large banking groups made up the vast majority of total complaints, with the four largest banking groups accounting for over half of all complaints.

Overall, the FOS received 1,631,955 enquiries in the period, meaning one in five progressed to complaints. This was over 100,000 less than the total amount received in 2015

Over the period, the service resolved 438,802 complaints, almost 100,000 more than it received.