Birmingham, back in English football's second-tier after being crowned champions of League One last season, took the lead in the opening match of the 2025/26 Championship campaign in the 53rd minute.
Jay Stansfield broke the deadlock when he followed up after Japan's Kyogo Furuhashi, previously a fans favourite at Scottish champions Celtic, hit the post.
Birmingham, whose minority owner is seven-time Super Bowl champion Tom Brady, dominated territory and possession as they recorded their 26th successive unbeaten home league game.
But at just 1-0 ahead there was always the risk of an equaliser and Ipswich, relegated from the Premier League, managed one with their lone shot on target of the match.
With five minutes of the eight added on having being played, an Ipswich corner to the far post was headed onto the arm of the unfortunate Lyndon Dykes, who did not appear to be handling the ball deliberately.
But Dykes' arm was raised and referee Andrew Kitchen awarded a penalty, with Ipswich's George Hirst scoring from the spot.
The goal sparked a brief fracas between the teams, with objects being thrown onto the pitch by frustrated Birmingham fans.