[4] A rugby league player in his early days, he discovered basketball as a 12-year-old at a holiday camp run by then-Auckland Stars coach Tab Baldwin.
[5] He also played for the Junior Tall Blacks in 2004, helping the team defeat Australia in the final of the Oceania Youth Tournament.
[10] He joined former Tall Blacks' head coach and childhood mentor Tab Baldwin at the club.
League rules meant he could return to the roster only if Penney dropped out, so Henry remained with the shadow squad for the rest of what was a championship-winning season.
[2] After helping the Saints win back-to-back titles in 2011, Henry was rewarded with a full-time contract with the Breakers for the 2011–12 NBL season, after Penney's departure to Spain.
[2][17][18] In April 2012, the Breakers defeated the Perth Wildcats 2–1 in the NBL Grand Final series to claim back-to-back championships.
[18] Following the Breakers' championship win, Henry joined the Otago Nuggets for the final six games of their 2012 New Zealand NBL season.
[22] In 2013, Henry played for the Southland Sharks[23] and helped them win the New Zealand NBL championship behind his Final Four MVP performance.
[47] However, following a revised competition format due to the COVID-19 pandemic and a subsequent player draft, Henry was acquired by the Auckland Huskies in June 2020.
[50] On 4 April 2022, Henry signed with the Franklin Bulls for the 2022 New Zealand NBL season, returning to the franchise he was originally set to play for in 2020.
[55] Henry earned his first selection to the Tall Blacks squad on 16 July 2009,[56] and participated in the 2009 FIBA Oceania Championship.