The country's biggest telecommunications provider says there's been a huge rise in scam calls over the past two months, likely prompted by even more remote working and time spent online.

Scams have cost Australians $22 million so far in 2021, according to the ACCC's Scamwatch service, with phone scams the most common.

Telstra's chief executive Andy Penn said the company has developed new automated systems to block the scammers.

"Blocking scam calls is no mean feat," he said.

The new technology was developed in-house by a team of six IT specialists, and has been rolled out across the Telstra network over the past four months.

It identifies call prefixes, and analyses call volumes from suspect destinations.

Almost 20,000 scams have been reported to Scamwatch this year, with dating and investment scams the most common.

Some of the more popular scam calls include "wangiri" or one-ring scams, or calls pretending to be from legitimate services, such as the tax office.

Telstra says customers who suspect they are being scammed should simply hang up.

Australian Associated Press