Australians have lost more than $1.2 million to NBN impersonation scams, with older people most likely to be fleeced.
Almost 1800 people reported being targeted by fraudsters up to September this year.
Australians aged 65 and over accounted for 81 per cent of the scams.
People living in NSW comprised almost half of all losses nationwide, followed by Queensland and Victoria.
The worrying data has been released by the Australian Competition and Consumer Commission's Scamwatch.
NBN impersonation fraud is usually carried out through remote access scams, one of the fastest-growing online crimes in Australia.
A scenario includes a scammer offering to fix a problem on a person's computer or device through remote access.
If the person follows instructions to download software, the scammer will gain access to banking credentials and transfer money out of the victim's account.
NBN chief security officer Darren Kane said scammers were becoming more sophisticated in their approaches and strategies to extort money.
"They know how to sound convincing, create a sense of urgency and frequently change their scripts to leverage the latest products and news from companies like NBN to build credibility," he said.
"The rule of thumb is if someone claiming to be from NBN contacts you to ask for access to your devices or offers to improve your internet speed for you, hang up on them and report it to the ACCC's Scamwatch."
STATE AND TERRITORY BREAKDOWN OF MONEY LOST TO SCAMMERS IN 2023
NSW - $601,482
Queensland - $227,939
Victoria - $172,171
South Australia - $89,594
Western Australia - $64,829
ACT - $54,500
Tasmania - $11,566
Northern Territory - $0
Not specified - $20,000