The Financial Services Authority (FSA) is monitoring promotions on financial service company websites as an investigation reveals that some promotions were misleading.
In an investigation of 77 websites the FSA found that a quarter "failed to sign-post key information" and as a result "failed to present information in a fair, clear and not misleading way."
The FSA said standards have improved since reviews in 2005 and 2007 identified problems but said it "will be carrying out a further review in March 2008 and will take action if it finds further failings."
Dan Waters, director of retail policy and themes at the FSA, said the internet is the favoured channel for many people looking 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," he said.
"Although many firms' website-based promotions are meeting our requirements, we expect the senior management of all regulated firms to ensure their customers are treated fairly - and we will be looking at promotional websites again early next year to make sure that firms have taken our findings on board and are taking website design seriously."