Career
Born in Lemington, Northumberland, Armstrong played as an amateur at Easington Colliery, before turning professional in November 1926 with Clapton Orient. At the end of the 1927-1928 season he transferred to Queens Park Rangers, before joining Watford on a free transfer in May 1933. Armstrong made over 200 appearances for Watford in all competitions, scoring twice.
He left the club in 1940, following the suspension of competitive football due to the Second World War.
Following his retirement from professional football, Armstrong worked for Universal Asbestos, and remained in their employment until shortly before his death.