Luke joined Northamptonshire for the 2018 season after a successful loan period with the County at the end of the 2017 season. He topped the batting averages for Lancashire when they claimed the title in 2011, the season after making the first of his 66 first-class appearances for the club. He scored 822 runs in 2016, with a career-best 137 against Hampshire but found opportunities limited so came to Wantage Road on an loan deal. During this time, he scored 82 from 94 balls in the County's last County Championship match with Leicestershire at Grace Road. During the 2018 season, Luke batted at the top of the order in the County Championship, to provide stability. As well as that, Luke proved to be a handy asset with the ball, picking up wickets in all three formats.