The versatile former Manchester United trainee’s new contract will give him the chance to add to his 127 appearances for the Blues.
The 29-year-old played 26 times for the club last term, having missed four months with a thigh injury.
Birmingham have also announced young goalkeeper Nick Townsend has been awarded a new two-year deal.
The 20-year-old has yet to make his Blues debut and spent the early parts of last season on loan at Conference side Lincoln, where he made 17 appearances.
Townsend’s deal comes with the option of a further year.