Kevin Costello, owner of Siam Imports, had a bad experience recently receiving payment with cash. A customer came into his store and paid with a fake $100 bill, but it turned out that the bill was actually a legitimate bill made into a counterfeit — and he failed to catch it.

"I had a couple other girls in here at the same time, so I didn’t really closely look at the $100, which if I would have did that I could [have] probably prevented it,” Costello said.

One reason he didn’t identify the issue on the spot: The counterfeit $100 was made using a clever technique thieves are favoring recently.

Unfortunately, Costello isn’t the only one to receive payment with phony money, as counterfeiting cases are on the rise in Hawaii, where he owns his business. Fake bills can cost business owners a lot of money, so it’s important to understand the dangers of this crime as well as how to identify fake bills — even if the counterfeiting is done well.

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According to Honolulu police, counterfeiting and forgery rose 16.5% in the past year.

While this counterfeiting can take on different forms, one popular method — and the one that applied to the bill Costello collected — involves taking $1 bills, bleaching them and reprinting them to look like real $100 bills.

"We’re seeing more and more of these bleaching of dollar bills and then they’re being printed with 50 or 100 on them,” Tina Yamaki, president of Retail Merchants of Hawaii, said.

One reason this approach is becoming common is that it can be really hard to detect. “It still feels kind of like a paper bill because you’re still using the same, you know, paper. It’s like if you throw money through the wash. Right? It still feels like a bill, but we’re seeing a lot more people now holding it up to the light, finding out that the [counterfeit detection] pens don’t always work,” Yamaki said.

It’s not just Hawaii where there is a concern. According to the Federal Reserve, around one in 40,000 bills is counterfeit, with high-denomination ($50 and $100) bills accounting for most of the fake money.

While this is a significant decline in counterfeit funds since 2006, when around one in 10,000 notes was thought to be fraudulent, this still means that as much as $30 million in fraudulent money is cycling through the economy.

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How to spot fake money

Costello feels that his mistake in accepting the fake $100 was driven by the fact that he simply didn’t take the time to look carefully enough at the bill. "Take the extra couple seconds, actually, all it would’ve took,” Costello said.

However, for those who aren’t as confident about their ability to tell a forgery, it’s helpful to review the nine guidelines from the Secret Service that can help you to distinguish when a bill is fake. Some of the features real bills include:

You can also look at the face plate number, the position of the letter and number on the note and the number designators placed on the bill by the Federal Reserve.

If you have any doubts, be sure to review the Secret Service guide, which includes pictures of each of these features, to help you determine if the bill is a legitimate one.

While it’s a pain to take the time to confirm all these details, it can keep you from accepting a bill that’s not a valid one and that vigilance can pay off both for you and for the rest of the economy.

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This article provides information only and should not be construed as advice. It is provided without warranty of any kind.