(NEXSTAR) — When you get cash, whether as change, from an ATM, or as a gift, do you ever think about where it’s been?

Americans are using less cash in recent years, according to a 2022 Gallup poll. While much of that was sparked by increasingly digital payment systems and venues going completely cashless, some of it can be attributed to COVID-19 (neither the CDC or the WHO ever advised against using cash to prevent the spread of the virus, but numerous places did away with it — a useless move, a study by BYU found, since the virus wasn’t viable on cash banknotes).

Even if plastic has become king, you can still find paper banknotes being passed around. Maybe you’ll even be lucky enough to find some green in a Christmas card this year. Or maybe you’re trying to find an elusive dollar bill that will be worth more than its printed value.

While it can be harder to know if the money in your hand is worth more than it looks, it isn’t terribly hard to find out where your cash has been, all thanks to a simple website launched almost 25 years ago: WheresGeorge.com.

If you aren’t familiar, Where’s George serves as a free tracking service for American banknotes. 

You may remember seeing stamps on dollar bills (of any denomination, not just those sporting George Washington) encouraging you to track them online with Where’s George. The stamp is no longer sold by the site, but the site itself remains up and running.

Where’s George was first launched on December 23, 1998, “for fun and because it had not been done yet,” according to the site’s FAQ page. The man behind it, Hank Eskin, said in a 2013 interview that the idea came to him as he stared at a chain-letter-like message written on a $10 bill. While the message promised good luck if Eskin were to write it again on another $10 bill, it was the bill’s serial number that caught his attention. 

After he determined nobody else had created a method to track money using serial numbers, Where’s George was created.

What are serial numbers?

A quick look at any U.S. banknote will show you a serial number. Those printed before 1995 have serial numbers consisting of eight digits sandwiched between two letters, like A12345678B. Today, only $1 and $2 bills follow this form, according to the Bureau of Engraving & Printing. Others have two letters at the front of their serial numbers.

You can already tell a lot from that serial number. The first letter on your $1 or $2, or the second letter on your bill of a higher denomination, refers to the Federal Reserve Bank that issued the note. The first letter on $5s, $10s, $20s, $50s, and $100s refer to the series of the note, the BEP explains. The last letter on any denomination is used to note “when all eight character serial numbers have been printed for a specific Federal Reserve Bank within the same series.”

Take, for example, the $1 bill below. According to its serial number, the Federal Reserve Bank in New York issued it (based on the ‘B’) and it was part of the first series. The $20 bill in the slideshow was issued by the Dallas Federal Reserve Bank (designated by the ‘K’) and part of the 2017A series (noted with the ‘P’). 

Unfortunately, that’s about where the tracking via the U.S. Mint ends. If you want to follow the money trail any further, you can turn to Where’s George.

Tracking your money

Bills dating back to series 1969 (or 1963, if it’s a $1 or $2), are tracked on the site. To start tracking a bill, you’ll be asked to input its denomination, bill series, serial number, your current zip code, whether you currently have the bill, and a short note about its condition or where you found it. Then, you can submit it into the system. 

After you release your bill back into the wild (meaning you spend it or pass it on to someone else), you can wait to see if anyone else enters it for tracking. In case you’re wondering, the $1 and $20 above have yet to be tracked.

The most entered bill, according to Where’s George, is a $1 bill from 1999. It has been entered 17 times, first in Minneapolis, Minnesota in 2008. Since then, it has traveled to Virginia; multiple stops in New York; Playa del Carmen, Mexico; California; Arizona; Wisconsin; New Jersey; Texas; Kansas; and, most recently, Washington. 

Overall, more than 28 million bills have been entered from California. New York and Florida have tracked the second and third-most bills at 21.6 million and 21.3 million, respectively. The District of Columbia has entered the fewest bills at about 737,500, followed by Wyoming at 764,300 and South Dakota at 970,800. 

Users from Noblesville, Indiana, have entered the most bills at 2.3 million, according to Where’s George’s database.

Ready to start tracking your money? You can find Where’s George online here — and yes, it’s free. Eskin tells Nexstar a new mobile app “is on the horizon” for Where’s George.