never. but maybe this year! 12-0 so far..
16 seasons (1992-2007)
the green bay packers
The Utes have had 2 undefeated seasons in their history. One in 2004, and one in 2008.
The Steelers have never had an undefeated season in their NFL history.
The University of Michigan Wolverines have 25 undefeated seasons.
i seasons with packers 1 with falcons 2 with vikings and 1 with jets 20 total
Packers! They are undefeated