The Panthers have gone undefeated in the preseason in three of the last four years.
Only one I think...
The Steelers have won six Super Bowls, but they have never gone undefeated during the season.
Two times, possibly three if they win the tournament tomorrow.
2 1950 and 1999
17 teams have gone undefeated in the regular season and of those only 1 (Indiana in 1976) has gone on to win the National Championship.
The Dallas Cowboys have never had an undefeated season.
the Colts have never gone undefeated,,,only two teams have.1972 Miami Dolphins (14-0)2007 New England Patriots (16-0)
Not sure if they are the top but university of miami went undefeated many, many times...id go with them