The 2004 Indianapolis Colts season was the 52nd season for the team in the National Football League (NFL) and 21st in Indianapolis. The 2004 Colts season began with the team trying to maintain or improve on their 12–4 record from 2003, and advance further into the playoffs. The Colts finished the season 12–4, and defeated the Denver Broncos for the second straight time in the playoffs, but they were halted in the Divisional round by the defending and eventual Super Bowl champion New England Patriots, their second straight loss in the playoffs to them. Peyton Manning had one of the best seasons ever by an NFL quarterback (and the best season of his Indianapolis career), throwing 49 touchdown passes and breaking the previous record of 48 held by Dan Marino. At season's end, Peyton Manning was named the NFL MVP. For the season the Colts set an NFL record with 51 total touchdown passes. The Colts led the NFL with 522 points scored. The Colts tallied more points in the first half of each of their games of the 2004 season (277 points) than seven other NFL teams managed in the entire season. Despite throwing 49 touchdown passes, Peyton Manning attempted fewer than 500 passes for the first time in his NFL career. Sports statistics site Football Outsiders calculates that Manning had the best-ever season by a quarterback, play-for-play, in 2004. The 2004 Colts are the only team in NFL history to convert five or more passing touchdowns in a game four different times during the regular season.

Offseason

Free Agency

During Free Agency, the Colts failed to re-sign linebacker Marcus Washington and cornerback Walt Harris. Both signed with the Washington Redskins in free agency.

NFL Draft

Undrafted free agents

Roster

Preseason

Regular season

Schedule

Standings

Game summaries

Week 1: at New England Patriots

Week 2: at Tennessee Titans

Week 3: vs. Green Bay Packers

Week 4: at Jacksonville Jaguars

Week 5: vs. Oakland Raiders

Week 7: vs. Jacksonville Jaguars

A fumble by Colts' TE Dallas Clark allowed the Jaguars to capitalize with a field goal, giving them a 16–14 lead as the fourth quarter began. In response, Manning led the Colts down the field to score a field goal, reclaiming the lead. On the subsequent drive, Leftwich connected with Smith for a 25–yard touchdown and then successfully targeted WR Ernest Wilford for a two–point conversion. The Colts quickly answered back, with Manning finding Harrison for a 39–yard touchdown that leveled the score. During the Jaguars' next possession, Leftwich completed two passes of over 10 yards, advancing into Indianapolis territory. On a 3rd–and–7, Leftwich located Wilford, which positioned the Jaguars within field goal range. K Josh Scobee then successfully converted a 53–yard field goal, allowing the Jaguars to take the lead with under a minute left in the game. With no timeouts left, the Colts were unable to mount a comeback, resulting in a 27–24 victory for the Jaguars, marking their first win in Indianapolis. This win propelled them to the top of the AFC South standings. This would ultimately be the Colts' sole defeat in their RCA Dome that season.

Week 8: at Kansas City Chiefs

Week 9: vs. Minnesota Vikings

Week 10: vs. Houston Texans

Week 11: at Chicago Bears

Week 12: at Detroit Lions

Week 13: vs. Tennessee Titans

Week 14: at Houston Texans

Week 15: vs. Baltimore Ravens

Week 16: vs. San Diego Chargers

Week 17: at Denver Broncos

Postseason schedule

Postseason results

AFC Wild-Card Playoff Game: vs. Denver Broncos

AFC Divisional Playoff game: at New England Patriots

Awards and records