The Alan Turing £50 banknote will be issued for the first time on June 23 2021, which coincides with his birthday, the Bank of England has confirmed.
The announcement was made as the Bank unveiled the design of the new polymer £50 note, which contains advanced security features.
The note will join the Sir Winston Churchill £5, the Jane Austen £10 and the JMW Turner £20, meaning all Bank of England notes will be available in polymer, which lasts longer than paper.
Often considered to be the father of computer science, Mr Turing played a pivotal role in breaking the Enigma code and his legacy has a lasting impact on the way we live today.
Born on June 23 1912, Mr Turing studied mathematics at King’s College, University of Cambridge, gaining a first-class honours degree in 1934. He was elected a Fellow of the College.
In 1936 his work On Computable Numbers is seen as giving birth to the idea of how computers could operate.
His “Turing test” also examined the behaviour necessary for a machine to be considered intelligent – the foundation for artificial intelligence.
Perhaps Mr Turing’s best-known achievement was his role in cracking the Enigma code.
It has been said this helped to shorten the length of the Second World War by at least two years – saving millions of lives.
The note, like the £20, incorporates two windows and a two-colour foil, making it very difficult to counterfeit, the Bank said.
There is also a hologram image which changes between the words Fifty and Pounds when tilting the note from side to side.
The new note, like the polymer £10 and £20, will contain a tactile feature to help vision impaired people identify the denomination.
People can still continue to use paper £50 notes as usual and notice will be given at least six months ahead of the date when the old paper £50 is withdrawn, the Bank said.
Bank governor Andrew Bailey said: “There’s something of the character of a nation in its money, and we are right to consider and celebrate the people on our banknotes.
“So I’m delighted that our new £50 features one of Britain’s most important scientists, Alan Turing.
“Turing is best known for his codebreaking work at Bletchley Park, which helped end the Second World War. However, in addition he was a leading mathematician, developmental biologist, and a pioneer in the field of computer science.”
Mr Bailey was asked later at a press conference how the Bank can ensure it has a diverse mix of figures on banknotes in future.
He said: “We’ve changed the process over recent times for selecting characters on banknotes.
“We’ve introduced far more public involvement but we’ve also introduced a framework for ensuring that we do over time have a diverse range of people on the banknotes…
“That is actually represented today by Alan Turing, because not only was Alan Turing a brilliant scientist but he was also a gay man who was treated appallingly and, of course, sadly, very tragically committed suicide.”
Asked if there are any plans for larger denomination banknotes, Mr Bailey said: “We haven’t got any plans to change the mix of denominations… we don’t see any need to raise the maximum value of the denominations.”
He admitted that, by the standards of some other countries, £50 is quite a low maximum, but added: “I think that’s appropriate. We don’t detect any demand for a higher denomination.”
Asked about the impact of coronavirus on the use of cash, Mr Bailey said: “The use of banknotes in transactions was declining steadily pre-Covid and of course it’s declined quite a lot more during Covid.
“But here’s the paradox: the total value of Bank of England banknotes in circulation has continued to rise.
“The £50 note is part of that story because, obviously, the £50 note is, we think, used by people as a store of value. So the demand for banknotes overall continues to rise.”
The new £50 note will feature the signature of Sarah John, the Bank’s chief cashier.
She told the press conference: “It’s important to realise that cash is still a really important means of payment for millions of people up and down the country.”
Ms John said £50 notes also support a lot of spending by tourists.
Director of GCHQ Jeremy Fleming said: “Turing was embraced for his brilliance and persecuted for being gay. His legacy is a reminder of the value of embracing all aspects of diversity, but also the work we still need to do to become truly inclusive.”