Fraudsters are turning to new technology to develop sophisticated ways of conning people out of money, the Office of Fair Trading has warned.
More than half of Britons aged 15 and over have been targeted, research for the watchdog reveals.
Consumers lose around £1 billion per year by falling victim to cons such as fake prize draws, 'psychic' mailings and premium-rate prize scams.
Launching scams awareness month, OFT chief executive John Fingleton said: "Consumers who lose money to scams have very little chance of getting any back.
"So it is essential that, in addition to enforcing the law against scammers, we equip consumers with the skills and knowledge necessary to avoid falling victim to them in the first place."
Some 28 million consumers are targeted every year by scams.