Police say they have received about 20 separate reports of counterfeit $50 notes being used in northern Tasmania over the past fortnight.
The notes, which all bear the same serial number HH 13863456, are a good likeness to the genuine article but they are slightly smaller, according to police.
The most identifying feature of the fake notes is the poor quality of the white stars in the clear window — they appear to have added by hand.
Police said there had been a rise in circulation of the fake notes in the Launceston CBD over the past 24 hours.
For anyone who suspects they have been passed a fake note, police advise to keep handling of it to a minimum and to store it in an envelope.
They ask any affected businesses to check their CCTV and to provide police with a copy of footage when reporting the matter.
Also, they ask people to complete the online Suspect Counterfeit Banknote submission form located at afp.gov.au.
Anyone with information should call Crime Stoppers on 1800 333 000.
