The Central Bank is warning of counterfeit bank notes during the Christmas shopping period.
The bank says that as the use of cash hits its peak, there is a corresponding increase in the opportunities for counterfeiters to pass off fake notes to unsuspecting consumers.
The Central Bank is advising people that when a real bank note is held up to the light, a picture and the value of the banknote become visible as a watermark, while a security thread can also be seen as a dark line.
It is urging shoppers to be extra vigilant and pass on any suspect notes to Gardaí.