Twenty five per cent of financial firms' websites present product information in an unclear or misleading way, according to a review by the Financial Services Authority (FSA).
The study found that several sites were difficult to navigate and often failed to display key information.
The FSA criticised some sites for giving the pros and cons of deals different levels of prominence and said it found product information that was out of date or inaccurate.
Key information on fees was also buried away in FAQ sections, while risk warnings were irrelevant to the product in question or not displayed clearly.
According to the FSA's Dan Waters:
"For many people the internet is the channel of choice for shopping around for financial products."
"However, it can expose consumers to high risk as they are able to make instant purchases without advice. This is why it is so important that firms' websites are fair, clear and not misleading."
The FSA said it had contacted the firms concerned and would be taking further action if the faults had not been corrected by the time it carries out a further review in March 2008.
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