If you've got $5 bills in your wallet or purse, you'll want to take a second look at them before spending them.
Despite there being over 826 million $5 bill notes in circulation today, some examples could be worth hundreds, if not thousands to currency collectors. It all has to do with their unique serial numbers.
According to GOBankingRates, $5 bills with serials such as "G88888888A” or "B55555555C" could be worth thousands due to them carrying a "solid" serial number — meaning all digits in the serial are identical.
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Only about one in 11 million $5 notes have a solid serial numbers, according to The Penny Hoarder. Which is why some sell for over $2,000.
If you find a note that has these rare characteristics, it is recommended to have it professionally appraised at your local coin shop.
Similarly to the $5 bills, there are other denominations that could be worth a lot to currency collectors.