Fraud costs the insurance industry up to £2bn a year, according to figures due to be released next month by the Association of British Insurers (ABI).
The ABI is set to release the actual figure on October 8, but a spokesman said previous estimates had under-estimated the extent of the problem.
Organised crime is said to be at the heart of a steep increase in the amount of fraudulent claims, with scams such as staged accidents and the same claim being made on a number of policies.
Fraudsters are said to have targeted the insurance industry more, as banks and retailers have tightened their controls on fraud.
But the ABI said the industry had been fighting back against fraud with tougher detection methods.
Experts say travel, household and motor insurance policies are the most frequently abused by criminals.