Westley, 37, is the club’s longest-serving player, having joined the Essex academy in 2003. He was appointed captain in January 2020, with Ryan ten Doeschate stepping down after the club’s County Championship and T20 Blast double-winning season in 2019.

He enjoyed initial success, guiding the team to the Bob Willis Trophy in 2020 – the red-ball tournament that replaced the County Championship during the Covid pandemic – and in 2025 he became the club’s all-time leading run-scorer in One Day Cup history.

However, this season’s campaign has been a more difficult one. Essex lost five Championship fixtures out of six from June to September, and were facing further defeat in their season finale against Glamorgan before rain limited play on the final day.

“Captaining Essex has been, and always will be, my greatest honour,” Westley said. “It has been a privilege to serve this great club, and it saddens me that I haven’t been able to leave it in a better place.

“Personally, I feel that my biggest value is scoring runs and contributing to Essex victories, something which I haven’t been able to achieve this year. For that reason, I feel now is the right time for a change and for the club to explore a new direction.

“It is an all-encompassing role which has been demanding at times, none more so than this current season, for which I will be accountable. No one is more disappointed than me with the results of the second half of the year.

“That said, I cannot express my gratitude and thanks to all the people who have supported me throughout this passage of my career. To the Members and supporters, who are the reason why this club is so special; to the past and current players; and to the coaching staff, I cannot express how truly indebted I am to you all.

“Above all, I want to thank my family, who have to carry the highs and lows along with me. Thank you.”

Chris Silverwood, Essex’s director of cricket, said: “We would like to thank Tom for his time as Club Captain. For six years, he has led Essex Cricket with immense pride, passion and commitment, and we are grateful for everything he has given to the role both on and off the field.

“Tom has been an important leader for the Club during his time as captain, and we thank him for his dedication and contribution in that role.

“A new captain will be announced in due course.”