The 62-year-old former Germany international attended the first day of his high-profile trial in Munich on Monday, charged with defrauding the authorities of €3.5m, and surprised the court by admitting the actual figure was much higher.
Hoeness is hopeful his belated honesty will save him from a criminal conviction.
"I am glad that everything is now transparent and on the table," he told the court.
"I deeply regret my misbehaviour. I will do everything to ensure that this distressing chapter closes.
"I have evaded taxes. I am aware that turning myself in to the authorities does not change that.
"I was hoping to escape criminal charges with a voluntary disclosure."
The trial has attracted widespread media attention - the court said that the 49 allocated press spots were filled within 27 seconds - and Hoeness had offered to resign from his post last May, only for his proposal to be rejected by the Bayern board.
If found guilty, Hoeness faces a possible jail term, with a verdict expected to be announced on Thursday.
