Elizabeth II, Pattern Twenty Pence, 1960sJames Callaghan, the then Chancellor of the Exchequer, made an announcement on 1 March 1966 that a decimal currency would be introduced. Prior to this announcement, on 19 December 1961 a Committee of Inquiry on Decimal Currency was established to advise on the denominations and designs of the new coins and it is likely that this is when this trial portrait by Arnold Machin was produced.

The Decimal Currency Act was introduced in 1969 and the decimal currency came into circulation on 15 February 1971, known as Decimal Day.