Duckett made his debut for Northamptonshire in the 2012 Friends Life t20 against Gloucestershire on 8 July 2012, whilst in his first year of A-levels at Stowe School.

He finished on the winning side in the final, and had particular success in the semi-final, scoring 84 off just 47 balls, and sharing a 132 run partnership with Alex Wakely.

[10] Duckett scored an unbeaten 53 off 38 balls to guide Nottinghamshire to a six-wicket victory in the 2020 T20 Blast final against Surrey.

[11][12][13] During the 2022 County Championship season he scored 1,012 runs at an average of 72.28, including three centuries, as Nottinghamshire won Division Two.

[19] In the sixth match against Sri Lanka A, he scored 220* off just 131 balls during an unbeaten second wicket partnership of 367 with Daniel Bell-Drummond.

[26] Duckett was deselected from the England senior team picked to face a Cricket Australia XI as part the 2017-18 Ashes tour following an incident in a Perth bar.

[31] On 29 May 2020, Duckett was named in a 55-man group of players to begin training ahead of international fixtures starting in England following the COVID-19 pandemic.

[32][33] On 9 July 2020, Duckett was included in England's 24-man squad to start training behind closed doors for the ODI series against Ireland.

He was seen as having the skill necessary for the so-called Bazball style of cricket adopted by the England team under Ben Stokes and Brendon McCullum.

[36] The decision brought immediate success with Zak Crawley and Duckett scoring the fastest ever England century opening stand (83 balls), and Crawley and Duckett scoring the fastest double-century partnership in Test cricket history (233 balls).

[41] In September he made his first One Day International century with an unbeaten 107 off 78 balls against Ireland at Bristol County Ground.