Cartwright signed his first professional contract in October 2017. Grant McCann stated "Sam is an excellent young centre half. He has taken my eye since I returned to the club, I have watched his progress through the age groups. He played a few games in pre-season and has been out on-loan at a variety of different clubs to get experience. He is someone that I believe has got a good future here."[2] The defender has had multiple loan spells, including at St Ives Town[3] and Kettering Town.[4] The defender made two senior appearances for the club in 2019 in the EFL Trophy, once against Arsenal Under-21s and once against Cambridge United.[5]
On 25 September 2020, Cartwright agreed to join National League club Woking on a short-term loan.[6]
On 11 May 2021 it was announced that he would leave Peterborough at the end of his contract.[7]
On 8 September 2021, Cartwright joined Spalding United,[8] following a short-term spell back with St Ives Town.[9]
Career statistics
As of match played 10 September 2024
Appearances and goals by club, season and competition