Complaints about Lloyds Bank, HSBC, Bank of Scotland and Barclays made up almost half the total number of complaints lodged with the Financial Ombudsman Service (FOS) in the first half of 2016.
Those banks received 43% of the overall number of FOS complaints between 1 January and 30 June 2016, with Lloyds Bank topping the table with 22,241 complaints in the opening six months of the year.
Bank of Scotland, which is owned by Lloyds Banking Group, was the second most complained about firm with 22,090 in the first half of 2016, followed by Barclays (18,603 complaints) and HSBC (11,082).
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In terms of products, complaints to the FOS about payday loans doubled in the first half of 2016 but PPI once again remained the most complained about product.
Today's figures from the FOS show that it took on 169,132 new cases between 1 January and 30 June – an increase of 3% on the previous six-month period.
Of these new complaints, 54% were about PPI, with 91,381 new cases involving PPI. This is down 1% on the previous six months, but still means PPI remains the most complained about financial product by far.
Last month the Financial Conduct Authority (FCA) announced it would be pushing ahead with introducing a time-bar for PPI complaints. It's thought that the deadline for reclaiming PPI will be June 2019 but it depends on the feedback the FCA gets in its latest consultation, which will close on 11 October this year.
For how to reclaim mis-sold PPI for free, check out our guide.
Payday lending complaints on the rise
Complaints not involving PPI have risen 8% to 77,751. The reason for this rise, according to the FOS, is that complaints about payday lending have more than doubled when compared with the last six months of 2015. This follows a huge 178% increase in complaints about payday loans over the last year.
Across all financial products, the FOS found in favour of the consumer in almost half of the cases it's sorted out so far this year (48% of the time). But across the 221 individual businesses the uphold rate varies from 3% to 92%.
'Complaints are moving onto a more even keel'
Earlier this year the FOS announced it had received its one-and-a-half millionth complaint about PPI – accounting for half of all the complaints it had received since being set up.
Chief ombudsman Caroline Wayman says: "The data we have published about complaints over the last decade or so helps to illustrates a challenging and volatile period for financial businesses. But the current signs are that complaints are now broadly levelling off and moving onto a more even keel.
"Although it's a few years now since PPI complaints peaked, we have been receiving over 3,000 a week for six years running – despite wider expectations that numbers will fall. And we're continuing to deal with the issues and uncertainties around PPI which remain a significant challenge for everyone involved.
"Lots of factors can influence the complaints we see, from more people knowing about their rights when things go wrong to external factors like volatility in the stock market or extreme weather conditions. That's why I believe it's important that we continue to share our insights into complaints to help businesses to avoid the mistakes of the past."