The original series of The Jetsons ended in 1963. Its first production run aired on ABC from September 23, 1962, through March 17, 1963.
The show’s original prime-time run lasted only one season and consisted of 24 episodes. Although it was cancelled after that season because of weak ratings, The Jetsons did not disappear from television. ABC moved reruns to Saturday mornings for the 1963–1964 season, where the program found a much larger and more lasting audience.
That broadcast history creates a common mix-up. Some references describe the original series as running through September 1963 because prime-time reruns continued until September 22 of that year. However, the original run of new episodes ended earlier, in March 1963. For a question asking for the year, 1963 is the accepted answer either way.
The franchise later returned with 41 syndicated episodes in 1985 and 10 more in 1987. Those later productions are why modern listings often show The Jetsons as a three-season, 75-episode television series rather than a one-season original.