On transfer deadline day, 1 February 2016, Powell moved to Hull City on loan until the end of the 2015–16 season. He made his debut on 20 February 2016 in the FA Cup fifth round match at the Emirates Stadium against Arsenal that ended in a 0–0 draw.
In June 2016, Powell was released by Manchester United, and in July 2016 was variously reported to be set to sign for Wolverhampton Wanderers and Wigan Athletic.
On 12 July 2016, Powell returned to Wigan Athletic on a free transfer, signing a three-year contract. On 13 August 2016, Powell scored in his first appearance of the season, in a 3–0 home win against Blackburn Rovers. His first season was seemingly ended prematurely by injury during a January 2017 FA Cup game against Nottingham Forest, but Powell returned to first-team action three months later, coming on as a substitute and scoring an injury-time winner against Rotherham United. On 13 April 2017, Powell scored an 11-minute hat-trick for Wigan, who were 2–0 down in the second half against Barnsley, earning his side a 3–2 home win. Powell continued his scoring momentum four days later, netting from the bench in Wigan's 2–1 away defeat to Brighton & Hove Albion on 17 April 2017. Despite scoring five goals in three consecutive substitute appearances, Powell's exploits weren't enough to help Wigan avoid relegation to EFL League One.