Ferres was a member of the England academy side that toured Australia and New Zealand in 2004. In 2005 he made 9 first team appearances for Bradford and was the regular goal kicker for the senior academy, a side he also captained, scoring 17 tries in only 17 appearances for the under-21s. As Super League champions Bradford faced National Rugby League premiers Wests Tigers in the 2006 World Club Challenge, Ferres played from the interchange bench in Bradford's 30-10 victory.
In late 2006, Ferres signed for Wakefield Trinity in exchange for David Solomona who went to Bradford.
Ferres signed for Castleford on 7 November 2008 after being released from his contract with Wakefield Trinity.
On 2 July 2009 Ferres signed a new 3-year deal to stay at Castleford.
In July 2012, Ferres signed for Huddersfield for a three-and-a-half-year deal. He was named at second-row in the 2013 Super League Dream Team. Immediately following the test series against New Zealand, Ferres was suspended by Huddersfield pending an investigation into his "conduct away from the club". He was consequently transfer listed.
In January 2016, Leeds Rhinos signed Brett Ferres from the Huddersfield Giants for an undisclosed fee.
Ferres won caps for England in 2006 against France, Tonga (2 matches) and Samoa in the 2006 Federation Shield tournament.
In 2013, Ferres was named in the English squad for the 2013 Rugby League World Cup. Ferres was selected after Gareth Hock's breached team policy and was removed from the squad. Ferres featured in every game England played.
In 2014, Ferres played for England in the 2014 Four Nations held in Australia and New Zealand.
In 2015, Ferres was selected in the England 24-man squad to take on New Zealand in a test-series. Before the series began England played a match against France. Brett scored 3 of the 15 tries scored by England in the match in what was a demolishing of their opponents.
In 2016, Ferres was initially selected in the England 24-man squad for the 2016 Four Nations, but had to withdraw due to a knee injury.
In December 2015 Ferres was suspended by Huddersfield for 'conduct away from the club'. It later emerged he had been having an affair with teams mate Craig Hubys wife. This led to Ferres becoming transferred by Huddersfield and eventually signing for Leeds.League Leaders' Shield: 2013
World Club Challenge: 2006
Baskerville Shield: 2015