How do I reliably detect counterfeit currency?

June 2, 2008 1:53 PM

How do I reliably detect counterfeit currency?

My mom lent a neighbor a very large sum of money last week, and she was paid back a few days later. She's concerned (because of how quickly it was paid back) that the money might be counterfeit. (The bills are a mix of new-design and old-design $50s and $100s.) How would we go about checking if the money is genuine or counterfeit? I've heard that those counterfeit checking pens are worthless. Would buying a random-off-the-shelf black light and using that to check if the money glows a different color work? Would that work for the old bills as well? Are there any other methods we could look into?

posted by yeoz to work & money (15 comments total)

There are probably guides for this online. Here are my two ideas, which both come down to "compare to known good bills."

Tear around and pull on the little polyurethane strip inside most bills these days. Test on known good bills of your own so you know what they're like.

Use a magnifying glass to see the tiny lines that make up the markings on bills. Those were hard to recreate, though not impossible.
posted by cmiller at 1:59 PM on June 2, 2008

There are machines that do this. Maybe you can take it to your bank and ask them if they can put it through a machine that can detect counterfits.
posted by underwater at 2:04 PM on June 2, 2008

Does the paper feel like money?

Can you see the security strips in the money (and when you hold the bills up to light, can you see printing like USA 100 repeated across the strips?)

On the new bills, does the color-changing ink change color?

When you hold the bills up to light, is there a watermark?

That said, the concern seems unfounded to put it politely. People who have access to large quantities of high-quality counterfeit currency don't need loans.
posted by Project F at 2:07 PM on June 2, 2008 [3 favorites]

(and they especially don't need loans from people who can say 'It was this person, at this address, who gave me these bills' if there's a problem passing one.)
posted by Project F at 2:10 PM on June 2, 2008 [1 favorite]

Just take it to your bank and have them check. Accusing someone of giving you counterfeit money from a guide on the web or whatever will cause you more problems than its worth. Even if you are right.
posted by damn dirty ape at 2:15 PM on June 2, 2008 [2 favorites]

The Bureau of Engraving and Printing has information on the safety features in Series 1996 $20, $50 and $100 notes and the the new $50 bill.
posted by andrewraff at 2:17 PM on June 2, 2008 [1 favorite]

I agree with damn dirty ape. Get a professional's opinion (i.e., the bank's). And then the police. You don't want to confront a counterfeiter yourself.
posted by desjardins at 2:28 PM on June 2, 2008 [2 favorites]

While working as a cashier, I always identified them by looking at the printing. Some fakes are better than others, but all the ones I've seen had poorer-quality printing than the real ones. I'm referring to sharpness of the lines, the readability of the microprinting, and the color-shifting quality of the ink on the newer bills. Use a magnifying glass if you need to.

And of course, look for all the safety features mentioned by other people.
posted by kidbritish at 3:25 PM on June 2, 2008

Just take it to your bank and have them check.

And be prepared for them to call the police if it is indeed counterfeit. They won't let you say "Okay thanks" and walk out.

Which is FINE, though. Just say "Thanks, I'd like to talk to the police now, too, obviously." and stay calm. :)
posted by rokusan at 3:25 PM on June 2, 2008

That's only a good idea if she's willing to rat out her neighbor, of course. I would, but I'm like that.
posted by Justinian at 3:31 PM on June 2, 2008

Does she have documentation that the money came from the neighbor? That way if she goes to the bank to have it checked, she can prove that she got it from that source.
posted by fructose at 3:46 PM on June 2, 2008

I agree with damn dirty ape. Get a professional's opinion (i.e., the bank's). And then the police.

These two sound like poor life decisions from which no possible good could come to your Mom besides possibly a slight piece of mind and large amounts of possible harm could come to her.

I think it unlikely the bills are counterfeit, but what if it was even mostly legitimate but included a couple counterfeits from circulation? I would check with the various methods people have and shall suggest and if the conclusion was legit or unsure, spend the money as cash. It can also be a poor idea for individuals in general to deposit large sums of cash in their bank accounts whether or not counterfeit. I don't know what I would do if the bills checked as fake to me.

Counterfeiting is bad, but it is not your mom's job to put herself at risk to stop it.
posted by TheOnlyCoolTim at 4:32 PM on June 2, 2008

After actually inspecting the money in person and hearing the backstory behind the loan from my mom just now, I don't think the money is counterfeit. I went through it all with a magnifying glass (that microprinting is so damn small!).

There was a deleted comment from cmiller (i think; idk; thanks mods!) about the possibility of money laundering, that made me think about it. The money was apparently supposed to be for the neighbor's kid and was to be used to pay off a loanshark (eek! my mom is an idiot!). The neighbor had given back the money without much of a real explanation why, which is weird if you ask me. I guess a slight possiblity exists that the money was obtained via less than legitimate means, and they might've been laundering money through Mom... I guess that's probably very unlikely though.

In any case, almost all of the money looks legit, except for four really really really old $50s that Mom will just spend as cash somewhere... (BTW, it was enough money to trigger a SAR, so I'm not sure I would've wanted her to deposit it at a bank all at once anyway...)
posted by yeoz at 5:52 PM on June 2, 2008

Just to elaborate on rokusan's answer: if you take suspicious looking money to the bank, and they confirm the bills are counterfeit, even if they don't call the cops, they will confiscate the money. They will not give the money back. They will not deposit the money into your account. They will not exchange the funny money for genuine bills.

My grandmother gave me a suspiciously fuzzy $100 bill for my birthday a few years ago, and instead of depositing it to my account, Chase Bank kept it and forwarded it to the Secret Service. I no more expect to see that money back from the feds than from my grandmother, who is now dead.
posted by hhc5 at 8:57 PM on June 2, 2008

Another give away is serial numbers on counterfeit bills. I know that is one thing that the banks look at when people bring bundles of notes in - if they are (almost) sequential than you should possibly get suspicious.
posted by cholly at 11:14 PM on June 2, 2008