Veteran striker Phillips and midfield duo Larsson and Bowyer are joined through the St Andrews exit door by Northern Ireland goalkeeper Maik Taylor, Czech defender Martin Jiranek and full-back Stuart Parnaby.
All six players have left the club on the expiry of their contracts. Blues confirmed, however, that the club has taken up the option of a one-year contract extension for captain Stephen Carr.
Spanish midfielder Enric Valles has also penned a new one-year deal despite missing most of last season with a foot injury following his arrival from Dutch side NAC Breda.
The club confirmed discussions over a new contract are ongoing with Scotland forward James McFadden, who missed most of last season with a knee injury.
Birmingham's acting chairman Peter Pannu told club website www.bcfc.com that the announcements are the result of boardroom discussions about the strategy of the club following their drop into the Championship.
"We have discussed strategies and player movements and policies,'' he said. "Suffice to say there is by and large consensus in the way we believe we should proceed."