The City watchdog has fined Credit Suisse £5.9m after uncovering failings related to sales of a complex investment product.
The Financial Services Authority enforced the fine over sales of Structured capital at risk products (Scarps) by the group's private bank between January 2007 and December 2009.
The regulator said Scarps "expose the investor to the risk that they will lose all or part of their initial capital".
Credit Suisse invested more than £1bn of its UK customers' money in Scarps during that period. The FSA said it had identified "a number of serious failings in the systems and controls in respect of those sales".
These included inadequate controls to assess its customers' attitude to risk, a failure to ensure that Scarps were suitable for certain customers, and failure to monitor that staff took reasonable care when advising on the products.
It said yesterday that in the wake of the discovery of the failings, Credit Suisse has enhanced the systems and begunan independent review.
Tracey McDermott, the acting director of enforcement and financial crime at the FSA, said widespread failings exist in wealth management "and standards need to improve".