1972 Miami Dolphins, and 2007 New England Patriots completed a perefect REGULAR SEASON.
Both teams remain undefeated til their respective superbowl (SB VII and SB XLII), However, only the 1972 dolphins won the super bowl to achieve a PERFECT SEASON, while the Patriots lost to the New York Giants
The 1972 Miami Dolphins are the only team to have completed an NFL regular season and the playoffs with a perfect record, going 17-0.
At that time, the NFL regular season was only 14 games long, not 16 as it is now. Because of this, the 2007 New England Patriots actually had a longer single-season win streak, going 18-0 before losing the Super Bowl to the New York Giants.
2007 Patriots 1972 Dolphins
One. The 1972 Miami Dolphins are the only NFL team to go undefeated in both the regular season as well as the playoffs. Four teams have had an undefeated regular season, 1924 Bears, 1942 Bears, 1972 Dolphins, 2007 Patriots. With the exception of the Dolphins, they all lost the championship game.
No NFL teams went undefeated in 2009.
Colts and Saints.
Colts and Saints.
1972 Miami Dolphins, that is it
There are no more undefeated teams left in the National Football League during the 2010-2011 season
Yes, the Dolphins in 1972 went undefeated during the regular season and won the Super Bowl. The 1934 and 1942 Chicago Bears went undefeated during the regular season but lost the NFL championship game both seasons. The Patriots just finished the 2007 regular season undefeated. The question was "Was there ever and undefeated NFL Season?" If you're referring to a regular season AND championship win...there was only one...the 1972 Miami Dolphins. If you're referring to and undefeated regular season only...four teams have done this...they are: 1943 Chicago Bears 1942 Chicago Bears 1972 Miami Dolphins 2007 New England Patriots Both of the above answers are inaccurate. The first team to go undefeated through an ENTIRE NFL SEASON and win the CHAMPIONSHIP was the Green Bay Packers in 1929. Curly Lambeau was their coach. The Dolphins were the 2nd team to do it, 43 years later, without resorting to any ties (NFL had tie games in those days and the Packers had 1 tie). The Packers and Dolphins are the ONLY teams to ever accomplish an undefeated NFL Championship.
2009
It is technically possible for three teams in one conference to have perfect seasons.
AnswerColts, Broncos and Saints as of 10-26-09.
Dolphins back in the day. 71 I believe