Born in Newcastle, New South Wales, Farrar played his junior football for the Western Suburbs Rosellas before being signed by the Newcastle Knights. He played for the Knights' S.G. Ball team in 2004, winning the 2004 S.G. Ball Cup Grand Final.
In 2005, Farrar joined the Parramatta Eels, winning the Premier League Grand Final in 2006.
In 2007, Farrar joined the North Queensland Cowboys. He played for the North Queensland Young Guns in the Queensland Cup.
In Round 7 of the 2007 NRL season, Farrar made his NRL début for the Cowboys against the Manly-Warringah Sea Eagles. He scored a try on debut.
In 2009, after playing 38 games for the club, Farrar made a mid-season move to the Manly-Warringah Sea Eagles in a player swap for Michael Bani.
In 2010, Farrar was thrust into the fullback position for the Sea Eagles after playing most of his career as a centre or wing following a season ending knee injury to team mate Brett Stewart. Despite not having played at the back since his junior days, Farrar generally impressed with his displays at fullback for the Sea Eagles.
On 14 September 2010, Farrar signed a 1-year contract with the Catalans Dragons in the Super League starting in 2011, alongside childhood teammate, Scott Dureau.
In 2011, Farrar signed a 2-year contract to return to the Manly-Warringah Sea Eagles in 2012. After two injury plagued seasons though, Farrar did not play a first-grade game.
In February 2014 Farrar signed a 2-year contract to play with the London Broncos in the Super League competition.
(For 2014 Super League season highlights, stats and results click on 2014 Super League season results)
Farrar has played for the New South Wales U19's team.
Farrar is the nephew of former Canterbury-Bankstown Bulldogs, Western Suburbs Magpies, Wigan Warriors and Illawarra Steelers player Andrew Farrar.