He has spent time on loan and dual registration from Hull KR at the Bradford Bulls and the Dewsbury Rams in the Championship, and Wakefield Trinity in the Super League.
[4] In the 2019 season, Milnes featured in the pre-season friendlies against York City Knights, Dewsbury Rams, Batley Bulldogs and Toronto Wolfpack.
Following the financial issues at the club, he signed for Hull Kingston Rovers along with four other Bradford players, however Milnes was loaned back to the Bulls for the 2020 season.
[citation needed] On 12 August 2023, Milnes played for Hull Kingston Rovers in their 17-16 golden point extra-time loss to Leigh in the Challenge Cup final.
[5] Milnes played a total of 18 games for Hull Kingston Rovers in the 2023 Super League season as the club finished fourth on the table and qualified for the playoffs.
[9] Milnes made his Castleford debut in round 2 against the Salford Red Devils,[10] and scored his first try on 23 March against the Batley Bulldogs in the Challenge Cup.