British banknotes and coins in circulation with the Queen's portrait will slowly be replaced by new printed and minted banknotes and coins bearing King Charles III portrait. The Bank of England has not yet given any details, saying that more will be known once the period of mourning has passed.
The Bank of England has already reassured Britons that current bank notes featuring the image of the Queen will continue to be legal tender, but with over 4.7 billion Bank of England notes in circulation, worth about £82 billion, it's unlikely to be a quick process.
In effect a portrait of King Charles III will first have to be chosen and distributed. It is expected that coins and notes will feature him facing west rather than east like the Queen, continuing a royal tradition started under Charles II in 1660, where the new monarch faces the opposite direction to their predecessor.
Replacing the existing notes and coins in circulation is expected to be a lengthy process, so will spending money with Queen Elizabeth II on, for some time to come. The Bank of England first issued its new polymer £20 note in February 2020 whilst the new £50 note was first issued on 23 June 2021, featuring the scientist Alan Turing.
The last day you can use the paper £20 and £50 notes is 30 September this year, meaning the process of recall and replacement has taken a total of 19 months.
The Queen appeared on Britain's coinage since 1953 and on bank notes since 1960, spanning decimalization, and the rise of the credit and debit card. Elizabeth II portrait was updated on five occasions since she took the throne in 1952.
New coins showing the first portrait of the Queen were issued in 1953. They represented a fresh start following the Second World War, and the portrait was used on the coins of the United Kingdom and the many Commonwealth countries.
Although decimalization did not happen until 1971, decimal coins entered circulation before then, with 5p and 10p pieces introduced in 1968 to replace the existing shillings and florins. To help the new coins stand out, a second portrait of The Queen was commissioned.