Born in Wellington, New South Wales, Peachey is an Indigenous Australian and the nephew of former Cronulla-Sutherland Sharks and South Sydney Rabbitohs player David Peachey.
He played his junior football for the Wellington Cowboys and Cronulla-Caringbah Sharks, before being signed by the Cronulla-Sutherland Sharks. Peachey played for the Sharks' NYC team in 2010 and 2011. At the end of 2011, Peachey was named at lock in the 2011 NYC Team of the Year.
In round 10 of the 2013 NRL season, Peachey made his NRL debut for the Cronulla-Sutherland Sharks off the interchange bench in the 30-20 win against the Canberra Raiders at Remondis Stadium. On 17 June 2013, Peachey signed a 2-year deal with the Penrith Panthers from the 2014 season. Peachey scored his first NRL career try in his last match for the Sharks in the 38-18 win against the Canberra Raiders at Canberra Stadium. Peachey played in 7 matches and scored a try for the Sharks in his debut season in the 2013 NRL season. On 22 September 2013, Peachey was named at lock in the 2013 New South Wales Cup team of the year.
Peachey went on to be part of The Cronulla side which won The NSW Cup in 2013 by beating Windsor Wolves 38-6 in the final.
In February 2014, Peachey was selected in the Panthers inaugural 2014 Auckland Nines squad. In round 1, against the Newcastle Knights, Peachey made his club debut with for Penrith Panthers off the interchange bench in the Panthers 30-8 win at Penrith Stadium. In round 12, against the Parramatta Eels at Penrith Stadium, Peachey scored his first and second tries for the Panthers in the 38-12 win. Peachey's strong start to the season for the Panthers finished in round 18 against the Brisbane Broncos at Penrith Stadium, after he suffered a season ending pectoral tear injury in the Panthers last minute 35-34 win. Peachey finished off his debut year with the Panthers with him playing in 14 matches and scoring 3 tries in 2014 NRL season.
On 13 February, Peachey played at second-row for the Indigenous All Stars against the NRL All Stars in the 2015 All Stars match at Cbus Super Stadium, the Indigenous side winning 20-6. On 3 May, he played for New South Wales City against New South Wales Country, playing at lock in City's 22-34 loss at Wagga Wagga. He finished off the 2015 season having played in 22 matches and scoring 5 tries for the Panthers.
On 26 September, he played for the Prime Minister's XIII against Papua New Guinea, playing off the interchange bench in his team's 40-12 win in Port Moresby. On 15 December, he was named on the interchange bench for the Indigenous All Stars team to play against the World All Stars on 13 February 2016.
On 13 February, Peachey again played for the Indigenous All Stars against the new World All Stars, playing off the interchange bench in his team's 8-12 loss at Suncorp Stadium. On 8 May 2016, Peachey played for NSW City Origin against Country, where he started at lock in the 44-30 win in Tamworth. In round 10, against the New Zealand Warriors, he scored a hat-trick of tries in the Panthers' 30-18 win at AMI Stadium. In the next match, in round 11 against the Gold Coast Titans, with scores at 24-all, Peachey went from hero to zero after he dropped a pass from Peter Wallace and didn’t dive on the ball. Titans halfback Ashley Taylor picked up the ball and raced downfield before Anthony Don acrobatically dived over in the corner one play later to seal a bizarre win at Penrith Stadium. In July 2016, Peachey was axed from the Panthers squad for their round 18 clash with the Cronulla-Sutherland Sharks after he returned training late after a night out in Cronulla. Peachey had planned to head back to Penrith in the morning but slept in and attempted to make it to training on time by catching a taxi with the trip costing him $250 and arriving in the clothes he was wearing the night before with no training gear. He eventually played in the Panthers NSW Cup team for the week. Peachey returned in the next match, in round 19 against the Parramatta Eels, playing at centre and scoring a try in the 22-18 win at Penrith Stadium. After Peta Hiku and Dean Whare suffered season ending knee injuries at the start of the season, Peachey was shifted from being a bench utility to centre. Peachey finished the 2016 NRL season with him playing in 24 matches and scoring 13 tries for the Panthers.
On 10 February 2016, Peachey played for the Indigenous All Stars against the World All Stars in the 2017 All Stars match, playing off the interchange bench in the 34-8 win at Hunter Stadium.