Career
At international level, he has represented the England semi-professional side on 13 occasions, scoring two goals. Southam began his career as a non-contract player at Fulham whilst also playing for Enfield, and also in Sunday league football for Edmonton Rovers. He then suffered a serious injury and was loaned to Boreham Wood to aid his recovery.
He made his Football League debut on 11 August 2007, in Dagenham"s first ever Football League game, a 1–0 defeat away to Stockport County.
On 11 May 2009, Southam was released by Dagenham and Redbridge after agreeing a mutual departure with manager John Still. Southam signed for League Two side Hereford United on 22 June 2009, he made six league appearances before leaving by mutual consent on 23 October, returning to former club Bishop"s Stortford.
On deadline day in the January 2010 transfer window, he joined Conference National club Histon on an 18-month contract. However, amidst financial trouble, Southam agreed a mutual termination of his contract at Histon at the end of the 2009-2010 season.
Southam joined Barnet in June 2010.
He made his debut on the opening day of the 2010-2011 season in a 2–1 loss at Chesterfield and scored his first goal for the club from the penalty spot in a 2–2 draw at Morecambe on 25 September 2010. He left Barnet at the end of the 2010-2011 season. In August 2011, he joined Dover Athletic on a one-year contract.
At the end of his contract in May 2012, Southam left Dover, signing for fellow Conference South side Eastleigh.
Southam left Eastleigh on 3 July 2014 and joined Conference South side Chelmsford City a week later. Southam made 13 appearances for England C between 2004 and 2007, including playing for England in the Home Nations Non-League International Tournament in 2007, located at several Scottish Highland Football League grounds.