Over £14bn worth of paper £20 and £50 banknotes will expire in exactly 100 days, with the Bank of England urging them to spend it before the deadline.
The legal tender status will be withdrawn from paper £20 and £50 notes, meaning they will soon no longer have any value.
The new polymer £20 featuring JMW Turner and the £50 featuring Alan Turing will be the only form accepted by retailers.
The Bank of England has set a deadline for September 30, 2022, for when the old paper notes will withdraw from legal tender.
“After this date, paper £20 and £50 banknotes will no longer be legal tender. So we are encouraging anyone who still has these to use them or deposit them at their bank or a Post Office during these last 100 days,” the BoE said.
There are still over £6bn worth of paper £20 featuring the economist Adam Smith, and over £8bn worth of paper £50 banknotes featuring the engineers Boulton and Watt, in circulation.
That’s more than 300 million individual £20 banknotes, and 160 million paper £50 banknotes.
“Changing our banknotes from paper to polymer over recent years has been an important development, because it makes them more difficult to counterfeit, and means they are more durable,” Bank of England’s Chief Cashier Sarah John said.
“The majority of paper banknotes have now been taken out of circulation, but a significant number remain in the economy, so we’re asking you to check if you have any at home. For the next 100 days, these can still be used or deposited at your bank in the normal way.”
The September deadline will also coincide with the one-year anniversary of the polymer £50 banknote featuring the scientist Alan Turing, on what would have been his 109th birthday.
The Turing £50 completed the family of polymer notes, with all denominations (£5, £10, £20 and £50) now printed on polymer.
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