Phineas and Ferb is an American animated musical-comedy television series created by Dan Povenmire and Jeff "Swampy" Marsh for Disney Channel and Disney XD. The program follows Phineas Flynn and his stepbrother Ferb Fletcher during summer vacation.

Season 1. S01E01 Rollercoaster. August 17, 2007. Disney Channel. While their mother is out shopping, the boys build a roller coaster. Dr. Doofenshmirtz and Perry battle due to the doctor's evil plan of throwing the earth off its rotation. S01E02 Lawn Gnome Beach Party of Terror! September 28, 2007. Disney Channel.

Watch the crossover "The Phineas and Ferb Effect" after you've finished season 4 and the movies. It's Season 2, episode 1 of Milo Murphy's Law. I'd say "O.W.C.A. Files" is optional and I personally don't think it's worth watching a second time, but you can check it out after you've finished season 4 if you're interested.

The following is a list of episodes of Phineas and Ferb. Because many of the 11-minute segments were originally aired individually, the episodes are listed in production order here. The first Phineas and Ferb animated short and the seventh Chibi Tiny Tales episode overall first aired on Disney...

The best order to watch Phineas and Ferb is the order in which the episodes were aired. There aren't any time leaps or anything weird, but there are numerous running gags, brick jokes, and subtle nods at continuity, so you should start with "Rollercoaster" and end with "Last Day of Summer"/"O.W.C.A. Files".