Barclays received 2,730 investment complaints in the six months to the end of June, of which only 37% were upheld by the firm. But this was only a fraction of the 442,226 received by Barclays Bank as a whole.
Next up, Santander UK was hit with 2,524 complaints and upheld 69% of them. The FSA reported a total of 240,597 complaints against Santander during the six-month period.
Meanwhile Lloyds TSB Bank was on the wrong end of 431,708 complaints in total, with 1,791 of these related to investments and just over a third (37%) upheld by the bank.
Bank of Scotland was also in the bad books, with the FSA recording 362,869 complaints in total, of which 1,735 had to do with investments, 58% of these were upheld.
Moving away from the banking behemoths, L&G portfolio management services was the recipient of 846 investment-related complaints and upheld 72% of them.
Scottish Widows Unit Trust Partnership also has a significant number, with 72% of the 559 complaints received upheld by the company.
Lastly Coutts & Co was hit by 1,135 complaints in total, with 104 related to investments within that. Of these 72% were upheld by the firm.
The FSA’s data is a summary of the information reported to the FSA by the financial institutions themselves and only includes those that have reported 500 or more complaints in a six-monthly reporting period. Firms are also required to publish the data on their own websites, the FSA said.