Seinfeld originally aired for nine seasons.
The sitcom premiered on NBC in 1989 and concluded in 1998, producing 180 episodes across its nine-season run. Its first season was unusually short, containing only five episodes, while later seasons generally had much larger orders as the show became a major ratings success.
The series was created by comedian Jerry Seinfeld and writer Larry David. It initially struggled to win NBC’s confidence: after the pilot, the network ordered only four additional episodes. Those episodes formed the rest of season 1, and the show gradually built an audience before becoming one of television’s most successful sitcoms.
The ninth season was the final one. Although NBC offered Seinfeld a reported $110 million for a tenth season, Seinfeld chose to end the series while it remained a top-rated program. The final season contained 24 episodes, including the two-part series finale, “The Finale.” The number nine is therefore a season count, not an episode count or the number of years between the premiere and finale.