The 26-year-old allrounder will complete the move at the end of the season after a 15-year association with the New Road club
Warwickshire have secured a deal to sign Ed Barnard from Worcestershire at the end of the season.
The Cricketer revealed Warwickshire were interested in signing Barnard earlier this month.
The 26-year-old was offered fresh terms to remain at New Road but instead has agreed to a three-year deal with their local rivals.
A product of the Worcestershire academy, Barnard's exit ends a 15-year association with the club which has included more than 200 appearances across the formats.
Notable achievements include helping the club win the LV=Insurance County Championship Division Two title in 2017 and the T20 Blast in 2018.
This season has included a career-best first-class score of 163 not out that helped beat Nottinghamshire at Trent Bridge.
"I'm extremely excited to join Warwickshire, it's a big opportunity for me," he said. "I want to be playing at the highest level and I hope I can do this and win trophies with the Bears.
Barnard on his way to 163 not out against Notts (Naomi Baker/Getty Images)
Barnard added: "I will be forever thankful to everyone involved with Worcestershire from back in my academy time to the present day.
"I've been very fortunate to have had the opportunities to represent this terrific club and develop into the cricketer I am today.
"I will always cherish the friendships and special memories made on and off the cricket pitch."
Worcestershire head coach Alex Gidman added: "It's obviously disappointing for our club, but we wish Ed well for the future.
"He has made significant progress in the last few years at Worcestershire and has become an integral part of our team in all formats.
"Ed wants to finish the season very well with us, and we look forward to enjoying our last few months with him before he moves on."
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