A Cumbrian factory is developing the new banknotes featuring King Charles III's portrait.
The first images of the new notes were revealed earlier, and they're planned to enter circulation by mid-2024.
CCL Secure in Wigton has been involved with all of the Bank of England's polymer denominations, including the first polymer £5 note in 2016.
The banknote substrate produced there includes some security features, but the colours and other printed elements are added elsewhere.
Neil Sanders, CCL Secure’s Vice President and Managing Director said: "The process involved close consultation and partnership with the Bank to ensure our team delivered on the expectations for the new substrate design."
As with all other Guardian™ polymer banknotes issued by the Bank of England, the new notes will be recycled once they reach their end-of-life; which is one of the reasons why polymer is the most sustainable substrate for banknotes.
Other proven benefits include an increased resistance to counterfeiting and heightened durability in the cash cycle.
Andrew Bailey, Bank of England’s Governor, said: "I am very proud that the Bank is releasing the design of our new banknotes which will carry a portrait of King Charles III.
"This is a significant moment, as The King is only the second monarch to feature on our banknotes."
All polymer banknotes carrying a portrait of HM Queen Elizabeth II will remain legal tender and co-circulate with the new notes.
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