Senior Sergeant Nigel Formosa said it appeared both males and females had been presenting the fake notes at shops, businesses and bars but they did not have firm descriptions.
"Shop owners and business people need to be aware of these notes and to contact police if they receive any," Mr Formosa said. " We're also very keen to find the people responsible for this, so any descriptions of people presenting them would be very helpful."
Only $20 and $50 notes were involved in the transactions at this stage.
People receiving what appeared to be a counterfeit note were advised not to accept it, and to take note of who was trying to pass it.
If a fake note was discovered it needed to be taken to police as soon as possible.
The notes which have turned up since Tuesday had been carefully packed up and were being sent to a specialist document examination centre in Wellington where they would be forensically tested.
"They pop up from time to time and retailers and businesses need to be on alert for them," Eastern District Police communications manager Kris McGehan said.
The last major spate was in September 2009, when $20, $50 and $100 notes began surfacing mainly at dairies and service stations in Napier.
Unlike the latest notes they were described at the time by police as "pretty good".
There had been some police successes in nabbing counterfeiters.
In 2007, three Taupo people were arrested and charged with being in possession of $4500 of counterfeit notes and "printing tools" which were found in their car.
They had been caught after a retailer spotted something odd about one of the notes he had been handed and took the registration of their car.
In the latest spate, police would be checking CCTV footage in areas where the notes were passed and were appealing for any one coming across a fake note, or any information where they were coming from, to phone 831 0700.