The 33-year-old midfielder has joined the Seasiders for an undisclosed fee and has penned a two-year deal at Bloomfield Road.
"I'm delighted to be here and I'm raring to go,2 Fergson told the official Blackpool website.
"As soon as I spoke to the manager my mind was made up.
"I saw a lot of Blackpool last year and played against them as well and I was very impressed."
Ferguson, who still had 12 months to run on his contract, made 84 appearances for Blues during his two year spell at St Andrews.