The 24-year-old, who shunned the opportunity to play for the Bundesliga club in the UEFA Champions League quarter-finals, is set to join the London outfit next month.
Chelsea had already agreed to a deal in principle with Werner after meeting his release clause of around €60 million ($68 million).
“He will link up with his new teammates in July, subject to passing a medical examination,” a Chelsea statement read on Thursday.
To everyone at @ChelseaFC :— Timo Werner (@TimoWerner) June 18, 2020
I’m incredibly happy to be joining the Blues next season! It feels like the right step for me and I am delighted to become a part of Chelsea FC. Really looking forward to playing for such a fantastic and historic club!
See you soon Chelsea fans! 👋 pic.twitter.com/WLcagJCHWt
Despite not having Werner when the suspended Champions League resumes in August, Leipzig wished him well, saying “we have grown up together."
Werner was with Leipzig when it made its top-flight debut in 2016, and he matched the club scoring record of 93 on Wednesday against Fortuna Dusseldorf.