If you are asking for the by fan vote and critical acclaim:
The central escape of Season 5, where Michael is held under the alias "Kaniel Outis" during a civil war. The 5 Off-Screen "Poseidon" Breaks
Michael Scofield officially breaks out of prisons on-screen during the Prison Break series and its sequel movie. However, according to dialogue in the fifth season, his total career count is at least nine successful escapes. On-Screen Breaks
Count (successful escapes by Michael Scofield): 3
Michael's first and most famous escape, which he planned for months and tattooed onto his body.