From time to time, we withdraw old banknotes after they have been replaced by a new version. All withdrawn Bank of England notes remain payable at face value for all time. They can be exchanged for new banknotes at the Bank of England, either in person in London or by post.
There is a different process in place for damaged or mutilated banknotes.
Withdrawal of the paper £5 note
Paper £5 notes will be withdrawn from circulation on 5 May 2017.
The only £5 note that will be legal tender after this date is the polymer £5 featuring Sir Winston Churchill, which was introduced in September 2016.
You can continue spending the paper £5 note, which features a portrait of Elizabeth Fry, until 5 May. After this date you can exchange them at the Bank of England in person or by post.
http://www.bankofengland.co.uk/banknote ... fault.aspx