The Bank of England have announced that they are starting to issue new King Charles notes, however the Queen Elizabeth notes will remain as legal tender and will be switched with the King Charles notes when they are used at banks.
The Bank of England wish to confirm that the King Charles notes are not fakes so citizens should not be concerned when they receive one, plus people do not need to take their current notes to the bank to change their Queen Elizabeth notes as they will remain as legal tender.

