Shotton has finally put pen to paper on a three-year deal after Boro boss Garry Monk confirmed earlier this month that a bid for the 28-year-old had been accepted.
“Boro have completed the signing of Ryan Shotton from Birmingham City on a three-year deal,” the Teessiders announced on their official website.
“Due to a confidentiality clause we are unable to disclose the fee in this deal.”
Shotton is Boro’s ninth permanent summer signing and joins the likes of Britt Assombalonga, Jonny Howson, Enes Mahmutovic, Martin Braithwaite and Ashley Fletcher at the Riverside, while Connor Roberts and Lewis Baker both arrived on loan.
The centre-half made more than 50 first-team appearances for first club Stoke after progressing through their academy and has had permanent spells at Derby and Birmingham.
He made over 50 senior appearances for Birmingham after joining them, initially on loan, in 2016 and has also had temporary spells at Altringham, Tranmere, Barnsley and Wigan.