While cash isn’t as commonly used as it used to be, counterfeit bills are still a problem. According to the Treasury Department, an estimated $70 million in counterfeit bills are in circulation, or approximately one counterfeit note for every 10,000 in genuine currency—although it could be much more than that. That’s why it can’t hurt to know how to spot a fake bill, especially if you work in the service industry. Here’s are some ways you can identify counterfeit bills:
- The feel of the paper: The easiest way to identify fake bills is by feeling the paper, which is grainy and crisp. Fake bills are often printed on regular paper made from tree cellulose, but real bills are made out of rag paper—a combination of linen and cotton fibers. Most people can intuitively feel the difference, especially when comparing a fake bill with a real one.
- Raised ink: The effect is subtle, but with real bills you can drag a fingernail across the surface and feel a bit of tooth or vibration from the raised ink, especially where there’s a lot of etching. Most counterfeiters struggle to replicate this effect.
- Color-shifting ink: On newer bills, the numbers on the lower right corner change color from copper to green on denominations of $10 and higher. Just tilt the bill back and forth and you should see it. Sometimes counterfeiters will use glitter so that the number alternates from a shiny to matte finish when you tilt it, but you can still tell it’s fake if the color doesn’t change.
- Watermark: When held up to a light, newer, legit bills will have a watermark of a numeral matching the bill, or alternatively, a ghostly image of the president depicted on the bill. The watermark can be seen from both sides of the bill.
- Security thread: Newer bills should have an embedded strip running vertically on the banknote, either to the left or right of the portrait (it depends on the denomination). The denomination of the bill will also be inscribed on the thread.
- Blurry printing: A sign of counterfeit bills is blurry lines or text, as real bills use die-cut printing that’s extremely precise and difficult to replicate. Blurry printing is best spotted by looking closely to see if the very small text that’s printed on the bill is clear and legible.
- Red and blue threads: It’s very subtle, but real bills have tiny, hair-like threads woven into the bill that appear blue or pink (personally, I think the blue threads are easier to spot). The lines are very thin which makes it more difficult for counterfeit printers to replicate.
- Ultraviolet glow: I haven’t confirmed this myself, but apparently if a legit bill is held up to an ultraviolet light, the $5 bill will glow blue, the $10 bill will glow orange, the $20 bill will glow green, the $50 bill will glow yellow, and the $100 bill will glow red. If you have a UV light, try it out and share what you find.
- Serial number: The first letter of the serial number should correspond to the year that the bill was designed, known as the “series” number, which is also printed on the bill. (For reference: E=2004, G=2004A, I=2006, J=2009, L=2009A, M=2013, N=2017)
For more on spotting counterfeit bills, check out this visual guide produced by the U.S. Currency Education Program.