Hey Jude 🎸 pic.twitter.com/SyjizjOQOl
— Borussia Dortmund (@BlackYellow) July 20, 2020
The 17-year-old has signed a long-term contract with BVB and will go straight into the first team squad.
According to reports in England, Birmingham will receive £25m (€27.5m) plus future bonuses.
Bellingham has taken the number 22 shirt and will start training with Dortmund on July 30.
He will then join his new teammates in a pre-season training camp in Bad Ragaz (Switzerland).
He explained his decision in an interview after joining the Bundesliga runners-up.
“I can’t thank Birmingham City enough for what the club has done for me,” said Bellingham. “Not just this season, but since I came to the club when I was seven.
“Now I’m really excited to join one of the biggest clubs in Europe. BVB’s path, but especially how they make young players improve, made the decision easy for me and my family.
“I can’t wait to play in one of the most beautiful stadiums in the world.”
Despite his tender age, Bellingham has already made 43 first team appearances for Birmingham, scoring four goals and delivering three assists.