Foster began his youth career at Brimsdown Rovers and later entered the academy at Premier League club Tottenham Hotspur,[3] progressing to sign his first professional contract in June 2002.[1] He failed to receive a call into a first team squad and was released at the end of the 2003–04 season.[4]
Dagenham & Redbridge
Foster dropped into non-league football to join Conference Premier club Dagenham & Redbridge in September 2004.[1] He made a breakthrough into the first team squad during the second half of the 2004–05 season and signed a new three-year contract in February 2005.[5][6] Foster was a regular during 2005–06 season and missed just one league match during 2006–07,[7][8] in which the Daggers secured promotion to the Football League after winning the Conference Premier title.[9] He signed a new two-year contract following the promotion.[10]
Foster continued to appear regularly for the club in League Two and made 69 league appearances and scoring three goals before being released at the end of the 2008–09 season.[11][12][13] During five seasons at Victoria Road, Foster made 186 appearances and scored four goals.[14]
Brentford
On 17 June 2009, Foster and former Dagenham & Redbridge teammates Sam Saunders and Ben Strevens joined newly promoted League One club Brentford on free transfers, with Foster signing a one-year contract.[13] He made 42 appearances during the 2009–10 season, in which the Bees trod water in mid-table before a strong finish elevated the club to a 9th-place finish.[15][16] He was given a free transfer at the end of the season.[17]
Wycombe Wanderers
On 25 June 2010, Foster and former Brentford teammate Ben Strevens joined newly relegated League Two club Wycombe Wanderers.[18] He made 41 appearances and scored one goal during a successful 2010–11 season,[19] in which the Chairboys secured an automatic return to League One after a third-place finish.[20] Foster signed a new two-year contract in May 2011,[21] but the Chairboys' return to League One was brief, with the club being relegated straight back to League Two at the end of the 2011–12 season.[20] After overcoming a shoulder injury,[22] Foster began the 2012–13 season as a regular,[23] before suffering a season-ending knee injury late in a match versus Rotherham United on 20 November 2012.[24] He underwent surgery in January 2013,[24] but failed to recover before the end of the season.[23] Despite being out of contract,[25] Foster remained at Adams Park into the early months of the 2013–14 season, but was forced to retire from football in November 2013.[26] In three seasons with Wycombe, he made 125 appearances and scored one goal.[14]
In May 2019, Foster was named as assistant to manager Steve Clark at Isthmian League Premier Division club Wingate & Finchley.[30] The pair departed the club by mutual agreement on 28 September 2019.[31]