Seasons

There are four seasons of Regular Show so far.

Season One (2010)
Season One consisted of 12 episodes and started on September 6, 2010 with The Power. It ended on November 22, 2010 with Mordecai and the Rigbys. There were no deleted episodes, though there was some deleted media from the last episode, listed above. The season durated in all endings of 2010 (except for December). The Unicorns Have Got to Go was the most popular season 1 episode with 2.417 million viewers total.

Season Two (2010-2011)
Season Two consisted of 28 episodes. It started on November 29, 2010, soon after the season finale of season one, with Ello Gov'nor. The season ended on August 1, 2011 with Karaoke Video. Like the first season, there are no deleted episodes, though some deleted media was in the last episode, listed above. First Day was the most popular season 2 episode with 2.364 million viewers total.

Season Three (2011-2012)
Season Three consisted of 39 episodes. It started on September 19, 2011 and as of now, there are no deleted episodes or media. The season ended on September 3, 2012. Stick Hockey was the most popular episode of season 3 was Stick Hockey with 2.000 million viewers.

Holiday Specials

 * Terror Tales of the Park (Halloween)
 * Butt Dial (Valentine's Day)
 * Big Winner (April Fool's Day)
 * Trucker Hall of Fame (Father's Day)

Season Four (2012-TBA 2013)
Season Four was confirmed on October 26, 2011 and started on October 1, 2012. This season will have 40 episodes in total and will end sometime in 2013.

Holiday Specials
This list is not complete.
 * Terror Tales of the Park II (Halloween)
 * The Christmas Episode (Christmas)

Trivia

 * Season One durated all endings of 2010 (except for December). It was the shortest season ever made, probably because 2011 was barely coming, so the season ended too early before 2011 began.