Kay joined EFL Championship team Barnsley's youth team from Fylde in February 2016[4] and made his debut in a Championship match against Bristol City on 29 October 2016.[5] He also spent time on loan at former club Fylde in March 2017, playing one game, and at Tranmere Rovers in November 2017, where he played two games, in addition to a trial game with Blackburn Rovers Under-23s in October 2017.
Chesterfield
Kay joined EFL League Two side Chesterfield on 4 January 2018.[6] He made his debut in a 4–0 defeat against Accrington Stanley on 6 January 2018.[7] His contract was not renewed by Chesterfield at the end of the 2017–18 season.[8]
Barrow
Following his release, Kay signed a two-year contract for National League side Barrow on 26 June 2018, joining former Chesterfield caretaker-manager Ian Evatt at the Cumbria club. Kay formed part of the National League title winning side of 2020.
He was one of three Barrow players to be offered a new contract at the end of the 2022–23 season.[9]
AFC Fylde
On 9 August 2023, Kay returned to AFC Fylde following their promotion back to the National League.[10]
Oldham Athletic
On 1 July 2024, Kay joined National League side Oldham Athletic on a two-year contract.[11]