The New Zealand allrounder has previously played for Derbyshire and Kent in the Blast, scoring 402 runs and taking 29 wickets.
Jimmy Neesham has joined Essex for the 2021 T20 Blast.
The New Zealand allrounder will join up with the Eagles after fulfilling his contract with Mumbai Indians in the Indian Premier League and will initially be available for the tournament’s group stage.
Neesham is a regular in New Zealand’s white-ball sides, scoring 1,644 runs and taking 86 wickets in 95 ODI and T20 appearances, and has played in numerous franchise leagues around the world.
The 30-year old has previously represented Derbyshire Falcons (2016) and Kent Spitfires (2017) in the T20 Blast, scoring 402 runs at an average of 26.8 while also picking up 29 wickets.
Commenting on joining Essex, Neesham said: "I am really looking forward to joining up with Essex Eagles for this year’s Vitality Blast.
"I’m excited about linking up with Ryan ten Doeschate again, having played with him for a few seasons when he was with Otago, and hopefully we can replicate the success of 2019."
Meanwhile, head coach, Anthony McGrath, added: "We sat down at the end of last season and concluded that we needed to add another all-rounder to the T20 squad, and with all of his talent and experience, Jimmy fits the bill perfectly.
"He’s excelled with both the bat and the ball on the biggest of stages for his country, as well as in the global franchise competitions and it’s a great match for both the player and the club."
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