Counterfeit detection pens are not always accurate and may give you false results. ... A counterfeit note cannot be exchanged for a genuine one, and it is illegal to knowingly pass counterfeit currency.

How accurate are counterfeit detection pens?

Basically, the only counterfeit bills which a counterfeit detector pen will detect are those printed on regular wood-based printer paper. And it does not even detect those 100 percent of the time, since there are easy chemical solutions to get around the pen detection test.

Can counterfeit money pass the pen test?

Can a fake bill pass the pen test? When you use a counterfeit pen, the solution may mistakenly cause fake bills to pass. For example, a common forgery method used to fool the pen test is to bleach lower denomination notes and reprint them as higher denomination notes.