Career
Harrison began his career with Darlington where he made 10 appearances for the club in the 2011-2012 season before joining Sunderland in October 2012 after a trial. He joined Bury on loan in November 2013 where he played once against York City on 29 December 2013. Harrison then joined Hartlepool United on loan for the remainder of the 2013-2014 season along with Sunderland team-mate Connor Oliver.
Harrison rejoined Hartlepool United for a second one-month loan spell on 22 August 2014.
He rejoined Hartlepool United on the 3 January 2015 for a third loan spell and on 2 February 2015 signed a permanent deal from Sunderland AFC to Hartlepool United.