With the Serie A team AC Milan, Pulisic, has agreed to a four-year contract extension.
He has 26 goals in 145 games for Chelsea and had a role in Chelsea's triumph over Manchester City in the 2021 Champions League final.
While just scoring once in his last season, Pulisic was deemed unnecessary at Stamford Bridge.
"The final three seasons at Chelsea were challenging. At a press conference for his introduction, he stated, "For whatever reason I wasn't receiving the opportunities I desired.
For me, the chance to go, start again, and play for such a successful team is fantastic.
Chelsea issued a statement wishing Christian well and thanking him for all of his services while he was a member of the team.
He spent the most money of any player in North America when he signed for Chelsea in 2019 after leaving Borussia Dortmund for £57.6 million.
He rejoins former Chelsea teammate Ruben Loftus-Cheek in Serie A after the latter joined Milan this summer.
Mateo Kovacic joined Manchester City, Kai Havertz signed Arsenal, and Mason Mount joined Manchester United.
Cesar Azpilicueta joined Atletico Madrid on a free transfer, and Kalidou Koulibaly, Edouard Mendy, and N'Golo all joined Saudi Pro League teams Al-Hilal, Al-Ahli, and Al-Ittihad.">