The use of the old £50 banknote design featuring Sir John Houblon is due is to stop from 1st May 2014.
The Bank of England has been withdrawing the banknote from circulation since its replacement was launched in November 2011. Those wishing to use their old banknotes can do so until 30 April, after which they will find the banknotes being refused as payment.
However banks including Barclays, NatWest, RBS, Ulster Bank and the Post Office have agreed to exchange the old banknotes until the 30 October 2014, though only up to the value of £200.
It is thought that there are 63 million old design banknotes still in circulation.
Source: BBC News