High-quality counterfeit money has reportedly been found all over Sydney, and police do not know how much of the fake cash is on the streets.
Businesses in several areas of the city have found counterfeit money, which is mostly $100 bills.
"They have been coated in a plastic resin to make them have a feel similar to a real note. They are pretty good," a police spokesman told the Daily Telegraph.
Some banks are even struggling to detect the fakes.
Already this year organised crime gangs have caused an increase in the amount of fake currency circulating, mostly $50 and $100 notes and mostly in the west of Sydney.
A man was charged with being in possession of $A520,000 ($640,000) in counterfeit cash just two weeks ago.
Like New Zealand money, Australian bank notes are made of polymer meaning they are harder to fake, but international crime syndicates are known to produce it on a mass scale.