King Charles £5 and £20 notes expected to sell for at least £13K and £20K

King Charles £5 and £20 notes are expected to sell for up to 1,000 times their actual values.

The brand new £5, £10, £20 and £50 bank notes have started being distributed across the UK, and certain notes will have a detail that will make its value sky rocket.

This is Money have revealed to the Daily Mail exactly what you should look for if you're lucky enough to stumble upon one of the new prints of King Charles.

There's one thing you need to check if you get your hands on a new note. (PAUL ELLIS/AFP via Getty Images)

Just last week, the new notes began to make their way into circulation, with eager collectors keeping an eye on the internet and in shops, as the reward could be absolutely colossal.

Some lucky ones have managed to find them and quickly put them up on eBay for a heavily inflated price, but the insane thing here is that they're actually selling for the listed amount.

It's all to do with the prefixes of the first new notes, and it turns out that each note has a desired serial number, and if it has it, you may have struck gold.

Essentially, for £5 notes, you're looking for a start of CA01, for £10 notes it'd be HB01, for £20 notes it'd be EH01 and for £50 notes, the magic prefix is AJ01.

Auctioneers Spink & Son spoke when the notes launched last Wednesday, revealing to This is Money that a simple fiver that had an 'unprecedentedly low' serial number was available to purchase at their auction.

If it's a low serial number, you're literally on the money. (Rasid Necati Aslim/Anadolu via Getty Images)

In fact, the most valuable £5 notes are those with incredibly low serial numbers that start with CA01, with several people on the hunt for these.

Though it's worth noting that the first two £5 notes with serial numbers CA01 000001 and CA01 000002 belong to King Charles himself and Queen Camilla.

A King Charles £5 note with the serial number CA01 000003 is up for auction on Thursday 13 June, and it is the lowest serial number of a new fiver note available to the public.

It has set a record as the lowest serial number it has ever auctioned at an auction of this kind, with the note set to be sold for an estimated £3,000 to £5,000.

However, experts seem to be more optimistic, with Simon Narbeth of bank note seller Colin Narbeth & Son claiming: "Without a doubt this note will sell for at least £13,000, if not more.

"This is the lowest serial number for a £5 note to be auctioned since a £5 note presented to former Prime Minister Harold McMillan in 1957 was auctioned in 2021, which also had the serial number 01 000003.

"That note sold for £22,000 at auction."

Wait until you see how much the rare £20 note goes for. (Rasid Necati Aslim/Anadolu via Getty Images)

For reference, a 2016 charity auction for the new fiver began with AA01 000017 as its lowest note, and that sold for an eye-watering £4,150.

If any of this peaks your interest, it's worth noting that the Bank of England has more charity auctions lined up this summer, including one for a tenner on 27 June, which Mr Narbeth says is 'even more exciting', as there is a lower serial number available on the note.

That's right, HB01 000002 is up for grabs, as number one lies with the King.

Narbeth estimates a cool £20,000 for that particular note.

The CA01 000003 note is the lowest serial number auctioned at Spink & Son, having once auctioned a note with a serial number of 01 000005.

It will be one of 152 rare £5 notes up for auction on Thursday, with estimates for the range of notes up for grabs lying between £150 to £5,000.