How to spot counterfeit money

The Secret Service advises taking any questionable large bill and holding it up to bright lighting. If it's a good bill, you'll see a hologram on the face-up side of the bill. Ideally, both of the images should match up perfectly. Looking through the light should reveal a thin vertical strip that tells you more. In the photo here, a genuine $100 bill is held above a counterfeit one.

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The U.S. Treasury offers this tip. Take any $10, $20 or $50 note and move it back and forth (ideally tilting it as you do). You should notice a number in the lower right-hand corner. If the bill's good, you should be able to see a shift in these colors.

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An easy way to tell if a bill is authentic is to hold it up to ultraviolet light. Each denomination glows in its own color. Find out what they are:

• $5 bills
• $10 bills
• $20 bills
• $50 bills
• $100 bills

If the bill doesn't appear as described above, you're holding a phony one.

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An authentic bill has serial numbers that are cleanly spaced and printed in the same color ink as the Treasury Seal (photos). With a fake piece of currency, the numbers may not appear as evenly spaced and may have a color different from that of the Treasury Seal.

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The U.S. Treasury has some advice if you encounter a phony bill:

1. Keep the bill in your possession but get a good description of who gave it to you and where. (How to describe a suspect.)

2. Write down the license or any other available identification number of the passer of the bill, if possible.

3. Contact your local police department or the Secret Service. (How to report fake money.)

4. Place the counterfeit bill in a safe packet or envelope.

5. Do not accuse or otherwise engage the bill passer. Leave that to the authorities.

If you own your own business or handle cash as part of your job, it's a smart move to buy an ultraviolet light (shop for one) or counterfeit detection devices (shop for one). Most business supply stores carry them; you can also buy them online.

Handling counterfeit cash isn't a game. If you suspect you possess a bad bill, take into account the person who gave it to you and call the authorities. Let the law enforcement professionals handle the rest.

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