2004–05 Seattle SuperSonics season

The 2004–05 NBA season was the SuperSonics' 38th season in the National Basketball Association. After losing their season opener to the Los Angeles Clippers 114–84 on November 3, the Sonics went on a nine-game winning streak as they won 17 of their first 20 games. Despite losing eight of their final ten games, the Sonics finished first place in the Northwest Division with a solid 52–30 record, marking their first 50-plus win season since 1998, and first playoff appearance since 2002. Ray Allen led the team averaging 23.9 points per game as he, and Rashard Lewis were both voted to play in the 2005 NBA All-Star Game in Denver. In the first round of the playoffs, the Sonics defeated the Sacramento Kings in five games, but would lose in the second round to the eventual NBA champion San Antonio Spurs in six games. This would be their final playoff appearance as the Sonics. Following the season, head coach Nate McMillan left for the Portland Trail Blazers, and Antonio Daniels signed as a free agent with the Washington Wizards.

For the season, they added new yellow alternate road uniforms they remained in used until 2008.