The 37-year-old will seek a new challenge going forward, following talks with the Trent Bridge club over future opportunities
Nottinghamshire batsman Chris Nash will leave the club at the end of the current campaign.
The 37-year-old was out of contract come the climax of the season and a mutual decision has been made to end his tenure at Trent Bridge.
Nash joined the club after 15 years at Sussex, scoring 1,703 runs across all formats since 2018.
However, opportunities in the shortened red-ball campaign have been limited, with just two outings coming in the Bob Willis Trophy.
The off-season arrival of Haseeb Hameed and form of Ben Slater and Joe Clarke has intensified competition for places at the top of the order.
In the T20 Blast, Nash has hit an impressive run of form, scoring 151 runs in six innings and he could yet sign-off with a trophy, with the Outlaws having comfortably qualified for the quarter-finals.
"I have really enjoyed my three years at Trent Bridge," said Nash, who reached 500 professional appearances in Thursday's win over Derbyshire. "From the moment I arrived, I have been made to feel part of the club by everyone involved.
"We are playing great cricket in the Blast at the moment and my focus is on continuing to contribute and on ending the season with a trophy.
"I feel like I still have a strong desire to perform and, for that reason, I am keen to seek a fresh challenge before moving into the next phase of my life."
Head coach Peter Moores added: "It feels like the right time for Chris to move on, as the competition for places has increased in the batting group over the last two seasons.
"He has been playing some of his best T20 cricket during the current season and his ability to put bowlers under pressure at the top of the order has been a key factor in our success so far."
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