Jacques O'Neill (born 8 May 1999) is an English professional rugby league footballer who plays as a hooker or loose forward for the York Knights in the RFL Championship.

He has spent time on loan and dual registration at the Leigh Centurions, Halifax, and the Sheffield Eagles in the Championship.

O'Neill signed a further one-year contract extension with Castleford in September 2020; head coach Daryl Powell said of him, "Attitude wise he is spot on.

"[14] A persistent hamstring injury severely disrupted his season, limiting him to just 6 appearances and forcing him to miss the 2021 Challenge Cup final.

[16][17] On 10 June 2022, Castleford announced that O'Neill had been released from his contract "to allow him to pursue another opportunity" of appearing on the ITV reality show Love Island.

[18] On 13 July, immediately following O'Neill's exit from the show, he visited a training session at the club, although regarding a return head coach Lee Radford said, "It is something we've not spoken about.

[22][23][24] Given his 18-month long absence from the sport and his previous hamstring issue, head physiotherapist Matt Crowther "worked closely with him to try and get him more mobile" and "durable" again.

[27] In August 2023, O'Neill joined the Sheffield Eagles in the Championship on an initial two-week loan deal, continuing on a rolling basis.

"[31] One year later, reflecting on his previous attempted return to rugby league, O'Neill said, "I was in a really bad place mentally and physically the worst shape of my life.