Bayliss attended Millfield School in Somerset where he was head boy, and played cricket, hockey and represented the school in triple jump, as well as playing rugby.[1]
The following season saw Bayliss play in wins over the Newcastle Falcons[4] and Ospreys[5] during the pool stage of the Anglo-Welsh Cup and on 30 March 2018 he started in the final of the competition as Bath were defeated by Exeter Chiefs to finish runners up.[6]
In March 2024, having made 110 appearances for Bath he signed a new three-year contract with the club.[7]
Bayliss was called up to the Scotland squad for the 2021 Six Nations Championship, qualifying through his Aberdonian grandmother.[10] Bayliss made his international debut on 7 November 2021 for Scotland against Australia in an Autumn International, when he came on as a substitute.[11] He made his first international start against Japan on 20 November 2021.[12]