Born in Preston, Lancashire, Charnock began his career at Wigan Athletic, coming through the club's youth system.
Charnock was released by Wigan quickly moving on to Football Conference side Northwich Victoria.
At the end of the 2006–07 season Charnock requested a transfer away from Northwich Victoria in search of league football and was sold to Peterborough United for an undisclosed fee.
[2] On 1 August 2012, Charnock joined Football Conference side Macclesfield Town on loan until January 2013.
[4] On 3 June 2013, it was announced that Charnock had signed for Stockport County, with whom he had spent a loan spell with at the end of the 2012/2013 season.