The Australian Tax Office (ATO) is warning Australians to stop and think before giving their personal details, or even their money, to anyone.
"The scammers are clever," the ATO's Kath Anderson said.
""Lately they've been imitating ATO phone numbers and projecting them onto caller ID. It's called 'spoofing' and it's designed to make you think that it's the ATO calling you."
Nearly 50,000 scams were reported to the ATO between July and October last year, with a five-fold increase from January to May this year.
The ATO has registered more than 17,000 scams this year alone.
This year alone, 113 Australians have handed over $1.5 million dollars to fraudsters, while 2500 people have given out some form of personal information, including tax file numbers.
The Australian Competition and Consumer Commission's Delia Rickard said it was becoming more and more common.
"This is happening all the time, every day," she said.
"Last year between scamwatch at the ACCC and ACORN there was over $300 million in losses reported from scams,"
The ATO's advice is to be aware of what personal information you share, and to keep devices secure by changing passwords regularly and keeping anti-virus software up to date.
Accounting service H&R Block's Mark Chapman said it should be obvious when a call is not from the ATO.
"The ATO does occasionally call people but they will never ever use threatening tactics to get money out of you," he said.
"If anybody does that, it's a scam,"
Filing a tax return could be complicated, especially if English isn't a first language and Mr Chapman says some translation may be required in order to properly file a tax return.
"The tax return itself has to be lodged in English, and any supporting documents that you have for deductions and so on, that also has to be in English, so you might have to get some translation done if you actually want to claim some tax deductions," he said.
Anyone who needs help, or who thinks they or someone they know has been scammed, should contact the ATO on 1800 008 540.