Season 21

Unreleased

Season 21 of premiered on PBS on Tuesday, October 24, 2017 with "Binky's 'A' Game/Brain and the Time Capsule" and "The Master Builders". Certain stations kicked off the season Monday, October 23, with Arthur and the Haunted Tree House, but others did not consider it part of the regular TV season.

Production began on September 9, 2015. This is the second season where the animation is entirely done by Oasis Animation, though it was produced at the same time as Season 20.

Together with Season 20, there will be 14 new 30-minute episodes. There will also be two one-hour specials that are not considered part of either season, though "Arthur and the Haunted Treehouse" will premiere alongside new episodes of Season 21.