To the untrained eye, a fake bill can sit inconspicuously among the other bills in one’s wallet. It can easily pass itself off as genuine, especially if you don’t know how to spot the differences between genuine and counterfeit cash. To avoid fake bills, you need to be familiar with the security features of paper currency and the signs of a cash forgery. Counterfeiters will try to reproduce or imitate those security features, but most counterfeiters can’t accurately mimic them anyway.
One security feature of money bills is the watermark. It is a faint replica of the portrait printed on the bill and is only visible from both sides of the bill if the bill is held up against strong light. For checking out the watermark, hold up the paper bill against the ceiling light. You can also use a desk lamp, or even a flashlight. While at it, also try comparing the quality and detail of the print, especially of the portrait. The print on genuine bills is usually sharp and crisp, with the details almost jumping off the paper. On counterfeit bills, the print may appear blurred and fuzzy; sometimes gaps may be noticeable in the small details of the print.
Another security feature that can be scrutinized when you suspect forgery is a plastic strip woven vertically into the bill itself. It is called the security thread. On the thin plastic strip is printed, in very tiny print, the denomination of the bill. You need a really good pair of eyes or a magnifying lens to see the fine print on the security thread.
The paper itself is yet another security feature. Red and blue fibers are often embedded into the paper. Reproducing the exact thickness and texture of the paper is hardly possible because the composition of the paper used for currency is kept under lock and key. Some counterfeiters try to mimic the red and blue fibers by printing red and blue lines on the bill, but the imitation can often be uncovered by closer inspection.
Also, you can check for color-shifting print on the bills. Most paper currency incorporate this security feature. The denomination print on the lower right-hand corner of $10, $20, and $50 bills, for example, change from copper to green when you tilt the viewing angle.
Besides the security features that can be examined using the naked eye, paper currency also has other security features that are not immediately visible without the help of magnifying lenses. One of such features is the fine print (also known as micro print) all over the bill. The fine print is difficult to replicate without advanced instruments. Yet, counterfeiters try anyway; so, it is worthwhile to also check for micro print. For example, the $50 bill has a series of very tiny “FIFTY” printed on its left and right borders.
There are other more advanced techniques for spotting fake money, but those described in this article are generally sufficient for the average person. Receiving fake cash may not be a criminal offense by itself, but it surely is hard-earned money lost.