The average amount lost by victims of online fraud has risen to £697 per person, says Verisign.
The security firm's Online Fraud Barometer revealed that's just almost double the average figure of £352, which was reported in March this year.
Verisign, which was purchased by Symantec earlier this year, said the number of UK Internet surfers that have been victims of online fraud remained at 10 percent. However, of these, 71 per cent said they suffered financially, with 15 per cent claiming to have lost more than £1,000.
More than four in five (82 per cent) of those that lost money through online fraud were fully reimbursed but of those that were not or only partially reimbursed, eight per cent believe they'll never see all of their money returned, which is double the number in March.
The report also revealed web users are becoming less security conscious, with 80 per cent claiming only to shop from websites with enhanced security features, that's two percent less than in the last report.
"While the rest of the country is working its way out of recession, the latest VeriSign Authentication Online Fraud Barometer shows how lucrative online fraud has become for cyber crooks," said Matthew Bruun from VeriSign Authentication.
"It's vital for consumers to appreciate how skilful these criminals are and take the appropriate measures to protect themselves online. Before inputting any personal details on a web site - whether it's their address, date of birth, or credit card information - consumers must take the time to check a site's security policies and credentials."
Bruun also urged web users to look out for security certificates and seals.