The Fresh Prince of Bel-Air aired 148 episodes during its original run. Those episodes were produced across six seasons on NBC between September 10, 1990, and May 20, 1996.
The season totals were 25 episodes in Season 1, 24 in Season 2, 24 in Season 3, 26 in Season 4, 25 in Season 5, and 24 in Season 6. Adding those figures gives 148, which matches the series overview and the episode numbering.
The total refers to the original scripted sitcom, not later reunion programming, clips, specials, syndicated edits, or the separate dramatic reboot titled Bel-Air. It also does not count the 2020 reunion special as part of the original NBC episode total.
The series became a long-running showcase for Will Smith, who played a fictionalized version of himself, and for the Banks family ensemble. Its six-season run included major cast changes, including Daphne Maxwell Reid replacing Janet Hubert as Vivian Banks and Ross Bagley joining as Nicky Banks.