Whether altering the design of ancient coins or making photocopies of bills with high-tech machines, counterfeiters have made illegal money throughout history. The Secret Service, an agency of the U.S. Treasury, has investigated suspected counterfeit operations since 1865. Over the past decade, the Secret Service has seized approximately 90 percent of all known counterfeit currency printed before it reached circulation.
In the printing process, the Bureau of Engraving and Printing uses complicated techniques to stifle counterfeiters. Beginning with the $100 bill in 1996, currency will be redesigned to include more security features. The following pictures explain how the Bureau protects your money.
The portrait on the bill is a lifelike picture, distinctly different from the screen-like background. Each portrait is only on one denomination. For example, George Washington appears only on the $1 bill, not on the $100 bill. Portraits on counterfeit bills appear unclear or unnaturally white.
Money is printed on high-quality paper made of cotton and linen. It has a strong "feel" to it, different from regular paper.
The artwork along the side of the bill has intricate, crisscrossing lines which are clear and unbroken. Lines in counterfeit bills are often smudged or broken.
Bills have tiny red and blue fibers that are embedded inside the bill.
The special "never-dry" ink that is used can be rubbed off. However, this isn't a fool-proof test since ink on some counterfeit bills also rubs off.
Beginning with series 1990, a polyester thread, which can't be reproduced by photocopiers, is woven inside $10, $20, $50 and $100 bills. USA TEN, USA TWENTY, etc., is printed on it to match the denomination.
"The United States of America" is printed in miniature letters around the border of the portrait. To the naked eye the words appear as a black line, which is also how photocopiers print them.
Since the consequences for passing counterfeit currency include fines up to $5,000 or imprisonment up to 15 years, you need to be careful. If you have a suspicious bill:
You are not reimbursed for turning in counterfeit bills; however, you protect yourself from trouble by following proper procedures.
Anti-Counterfeiting: Security Features, via the U.S. Treasury, Bureau of Engraving and Printing
Know Your Money, via the United States Secret Service