Estcourt began her career at Reading, joining the club's youth academy at the age of nine. In 2011, Estcourt left the club to join Chelsea but returned to the Royals four years later at the age of 16.[1]
At the start of the 2016 season, Estcourt joined Bristol City on a short term loan,[2] spending three months at the club where she made 10 appearances scoring twice.[3] When Estcourt returned to Reading, she signed her first professional contract.[4] Estcourt then returned to Bristol on a season long loan for the 2017/18 season. In June 2018 Estcourt signed a two-year contract with Reading keeping her at the club until the end of the 2019/20 season. On 8 June 2020, Reading announced that Estcourt had left the club after her contract had expired.[5] In September 2022, it was confirmed Estcourt had joined Birmingham City from Coventry United.[6]
Estcourt made her full international debut on 6 March 2015, at the age of 16, against Bosnia in the Istria Cup.[9] During a European Qualifying match v Israel in September 2016 she scored her first international goal leading to comparisons with the goal scored by Hal Robson Kanu against Belgium in Euro 2016. She has gone on to make 36 senior appearances scoring 3 goals.