Here are the coveted serial numbers to look out for12:58, 05 Jun 2026Brits are encouraged to check any new banknotes they receive, as they could potentially be worth a small fortune. An expert suggested that notes bearing King Charles III with low serial numbers could fetch “thousands” when sold to collectors.‌In a video posted on TikTok, an expert known as the Coin Collecting Wizard revealed what to look out for. The coveted notes can include £5, £10, and £20 notes.‌But, it is crucial to inspect their serial numbers for those that are particularly desirable among collectors. This number is located at the bottom right corner on the reverse side of the note.‌Generally, the lower the serial number, the higher the value of the note, although certain other numbers and patterns are also sought after. The expert’s video was originally made public in 2024, when the Charles III notes were first released.Content cannot be displayed without consentHowever, he recently re-posted his advice, as it is still relevant today. The video said: “New banknotes featuring the portrait of King Charles III have now entered circulation, but it may be some time before they are commonly seen in wallets and purses.‌“The king was presented with a full set with the lowest serial numbers following the tradition of the monarch receiving the first issues of new banknotes.” He stipulated that notes with lower serial numbers will be worth more.He continued: “And collectors will be seeking banknotes which come as close to the 00001 serial number as possible. So what you need to be looking for is low serial numbers or even certain patterns to your serial numbers as it has been known for these to sell for thousands of pounds in the past.“So when you do finally come across one of these new King Charles banknotes, make sure to check those serial numbers as you never know.” In an earlier video, the specialist elaborated on the varieties of serial numbers worth seeking out.‌He explained: "Notes with very low serial numbers, especially ones beginning with a 'AA' or '1' tend to attract the most interest as these are from the very first batches printed."Other desirable serial numbers include repeating patterns like '123456' or '11 11 11 11', palindromic numbers eg '2002' and numbers with historical significance such as his birthday."‌He shared some specific numbers that could be particularly sought after:123456AA01222222221000003On its website, the Bank of England confirmed that the serial number of a note is important to collectors. It said: “Ignored by many, the serial numbers on our banknotes are one of a number of features that can spark huge interest among banknote collectors.Article continues below“When we release a new banknote, we hold back some of the first printed notes with especially low or symbolic serial numbers. We donate these to people and institutions that were involved in the development of the note or who traditionally receive a note when a new series is issued.”These are often auctioned off for charity with an auction of newly released £20 notes in 2020 raising a combined £143,420.