The 65th Episode Rule was a controversial rule that applied to all Disney television shows, particularly during the late 1990's and early 2000's stating that no show can go beyond 65 episodes (2 or 3 seasons). This rule angered many Disney Channel fans, due to the fact that many shows had been canceled while they still had a large fanbase (such as Lizzie McGuire and Even Stevens). After initially ending after 65 episodes on February 22, 2005, Kim Possible was renewed for a fourth season on November 29, 2005, making the show the last to be subject to this rule. No other show on the network has been canceled due to this rule.

Exceptions to the rule

As of 2018 Marvel's Avengers Assemble officially broke the 105 episodes (4 season) rule with its fifth season Marvel's Avengers Black Panthers Quest premiering September 23, 2018. The fifth season is aimed to air 26 episodes making the total 129 episodes. As of 2015, the combined run of The Suite Life of Zack & Cody is the longest-running show, at 158 episodes and a movie.

Although Gargoyles is listed as an exception to this rule, it should be noted that the show's last twelve episodes, aired as part of the show's third season (subtitled The Goliath Chronicles), are not considered canon by creator Greg Weisman, unlike the first episode of that season, "The Journey" (which was later adapted as the first two issues of the 2006 Gargoyles comic book). As such, the canon run of the Gargoyles TV show is actually 66 episodes long, just narrowly making it an exception to this.

Recess could technically be considered another exception to the rule, as ABC wanted to order more episodes for the 2002-03 season. However, Disney declined on making another full season's worth of episodes. Only four new episodes of Recess were made, bringing the full count up to 69, but they were never actually aired as episodes of the show; instead, three of them were released together as Recess: Taking the Fifth Grade, while the last one was released as part of Recess: All Growed Down.

The rule officially ended in August 2004 when Disney Channel ordered 13 additional episodes of That's So Raven, after the show had filmed its 65 episodes.

Kim Possible originally ended after 65 episodes, with the movie So the Drama intended to serve as the show's last three episodes (though in the United States, five other episodes from the third season were held over and aired after the movie's premiere). Due to popularity, the show was picked up for a fourth and final season. This is considered the turning point for the rule being phased out. Since then, the only Disney show that ended at exactly 65 episodes was ANT Farm in March of 2014.

Rationale

The cut-off point of 65 episodes may have more to do with programming schedules than any personal feelings about a series on the part of studio executives. With 65 episodes, one episode can be broadcast each weekday, reaching the 65th episode at the end of the 13th week (5 x 13 = 65). Thirteen weeks is one quarter of a year. Four 65-episode shows can be broadcast in a calendar year.

At the time the 65th Episode Rule came to the public's attention, networks were beginning to move away from rigidly-defined schedules, where a weekly show would run for 13 or 26 weeks straight, followed by the same number of repeats. This change has further been accelerated by the following factors:

Dedicated channels such as Disney Channel, Cartoon Network and Nickelodeon, rather than relying on syndication to fill afternoon and weekend morning programming times.

More ratings-driven decisions and fewer instances of allowing shows to find an audience even if the ratings are not as high as desired.

Shows being cancelled before a current season is completed, requiring a midseason replacement to replace the show that was cancelled.

New technology like DVRs, Video-on-Demand and episodes being made available on network websites, which allow viewers to watch shows on a schedule of their choosing.

Currently, the number of episodes in a season varies from show to show, with 18 to 39 being the current range for a "full" season. In addition, a season can be split into two segments, with the second segment being referred to as a half season (season 1.5, season 3.5, etc.) or even as a "new" season. All of these factors make it difficult for a modern show to reach the 65-episode mark any longer and can just as easily end with fewer episodes as having more than 65 episodes.