Paper £20 and £50 note withdrawal will occur on Friday the 30th September 2022 – this is the last day that you can legally use paper £20 and £50 notes as they will be completely replaced by new polymer versions as of this date.
“We will withdraw legal tender status of our paper £20 and £50 notes after 30 September 2022.
If you have any paper £20 or £50 notes, we encourage you to use them or deposit them with your bank or Post Office before 30 September 2022.”
For more information -> Paper £20 and £50 note withdrawal | Bank of England