Born in Bromley-by-Bow, London, two-time England Schoolboy international Allen was on the books at Tottenham Hotspur before leaving to join Leytonstone in 1932 and then rekindled his Football League career at Clapton Orient in 1933 where he made one appearance.
He scored six goals in 31 games for the club during his single season before moving back to London with Brentford, where he failed to make a first-team appearance.
During the war years, Allen made guest appearances for Port Vale and then Northampton Town before joining the latter when League football recommenced following the hostilities.
[2][5][6] As a youth, alongside appearing for England Schoolboys, Allen played tennis at Wimbledon and was a renowned London Schools sprinter but opted to pursue a football career.
Colchester arranged a benefit match with Bedford in September 1952 to help aid his family's immediate financial concerns, with a gate of 4,500 in attendance.