Brits urged to check bank notes for one tiny clue that they could be in for a lot more money

Even though a lot of places are going cashless now, we still love a good crisp note in our purses - and it's worth giving them a thorough look over, because you could be sitting on a goldmine.

Earlier this month, we told you all about the importance of examining your notes if you're lucky enough to have gotten one with King Charles' face on.

The King, who had his coronation in May 2023, features on the new £5, £10, £20 and £50 notes.

If you're one of the lucky few with a rare note, you're tipped to make thousands of pounds in profit.

This is Money told the Daily Mail about what we should be keeping an eye out for when examining the notes - and you need to be checking the serial numbers.

The first ever printed notes featuring King Charles feature the serial numbers CA 01 000001 (£5), HB 01 000001 (£10), EH 01 000001 (£20) and AJ 01 000001 (£50).

King Charles now features on our cash. (DANIEL LEAL/AFP via Getty Images)

It is very rare to come into contact with a note that has a serial number below 20.

For context, a £5 note with an 'unprecedentedly low' serial number landed in the possession of auctioneers Spink & Son.

Simon Narbeth of bank note seller Colin Narbeth & Son declared: "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."

It boasted the serial number CA01 000003.

So, checking your money is all the rage right now.

The blue smudge runs through the serial number. (Invaluable.com)

In other money news, it turns out that a £20 note has been listed at auction with an estimated value of £75 - so it's worth seeing if you're in with a chance of more than doubling your money.

Imagine the heartbreak if you just spent it at Sainsbury's.

It turns out what you should be on the lookout for is a smudge.

Yep, the reason behind someone's £20 becoming £75 is a smudge - which can be seen running through the serial number.

The note in question was put up for auction by London Coins earlier this month, on 3 June.

This isn't the only example of seemingly regular cash being auctioned for much higher prices.

A £5 note recently fetched a high price.

It was missing the signature that's a given on all notes, making it very rare indeed.

It sold for a whopping £170, which is what we call getting bang for your buck.