While many are alert to scam telephone calls, the culprits have moved to SMS to catch unsuspecting people in their path.

The majority of losses between January 1 and May 1 were to investment scams with $158 million lost - an increase of 314 per cent on the same period last year, according to the Australian Competition and Consumer Commission.

Most losses to investment scams involved cryptocurrency investments, with $113 million reported lost this year.

"We are seeing more money lost to investment scams and so are urging all Australians not to trust investment opportunities that seem too good to be true," ACCC Deputy Chair Delia Rickard said.

"Australians should be very wary of anyone asking them to invest in or transfer money using cryptocurrency, especially if it's someone you have only met online."

Impostor bond scams increased this year, with $10.9 million reported lost. They usually involve someone impersonating real financial companies or banks and claim to offer government or Treasury bonds, or fixed term deposits.

Phone scams have almost halved but scam text messages are up 54 per cent as the most common contact mode.

Those figures suggest the Reducing Scams Call Code 2020, that blocks incoming calls from scammers is having an impact.

New rules to block scam text messages will also be introduced later this year.

The ACCC says its research shows only 13 per cent of people report their losses to Scamwatch.

Australian Associated Press