Financial services firms received 1.86 million complaints in the first half of this year and paid out £243 million in redress, according to the City regulator.
The Financial Conduct Authority (FCA), which published the figures on its website, said that since complaints about payment protection insurance (PPI) peaked in 2020, half-yearly complaints have remained relatively constant at between 1.8 million and 2.0 million.
Complaints related to pensions, insurance and investments increased between the second half of last year and the first half of 2024, the regulator said.
Banking and credit cards and home finance-related complaints fell over the same period.
It's vital that businesses are open and transparent with their customers, treating them with fairness and understanding
The FCA said there were decreases in the three most often complained about products: current accounts; motor and transport-related gripes; and credit cards.
Some 492,557 current account complaints were reported in the first half of this year, down 4.5% compared with the previous six months.
There were 276,469 motor and transport-related complaints – a 1.7% decline on the previous six months.
And 222,529 credit card complaints were recorded – a 4.4% fall compared with the previous six months.
Overall, the percentage of complaints that were upheld by firms remained at 57% between the second half of 2023 and the first half of 2024.
The average redress paid for upheld complaints in the first half of this year was £201.
The figures were released as the Financial Ombudsman Service (FOS), which resolves disputes between consumers and firms, reported that the complaints it has been seeing jumped by more than 40% in the first half of this year compared with the same period last year.
It received 133,019 complaints between January and June 2024 compared with 93,114 complaints in the same period in 2023.
Banking and credit continues to be the most complained about sector, the service said.
In the first six months of 2024, consumers lodged 101,031 banking and credit complaints, including disputes about credit cards and unaffordable lending, car finance woes as well as fraud and scams.
Over half of all banking and credit complaints were brought by professional representatives.
Abby Thomas, chief executive and chief ombudsman at FOS, said: “Businesses should put consumers at the heart of their service but the high level of complaints we receive shows that’s not always the case.
“It’s vital that businesses are open and transparent with their customers, treating them with fairness and understanding.
“Whilst professional representatives have an important role to play, they must ensure that their cases are well evidenced and have merit.
In the first six months of 2024, the FOS upheld 35% of complaints in consumers’ favour, compared with 37% in the first half of 2023.