Callum Webb played for Norwich's Under-21s ina friendly against Enfield Town in August 2012. Defensive-minded midfielder Webb, who is a Republic of Ireland youth international, made 27 appearances for Arsenal's under-18s, scoring twice, and also made two substitute appearances for the Reserves in the 2010/11 season. In the summer of 2011, he was expected to join leicester but instead joined QPR, whom released him in May 2012.

He signed for non-leaguers Bishops Stortford in October 2012. On 4th July 2013, he signed for Welling United.

In December 2013, Webb was loaned, along with teammate Josh Ekim, to Ryman League side Billericay and both scored on their debut in a 2-1 win at Margate on 10th December 2013.