Moises’ career has included guest appearances on shows such as Everybody Hates Chris, The Suite Life of Zack and Cody, and a recurring appearance as Rico on Hannah Montana, where he became a series regular in the show’s second season. As a regular on the Disney Channel, Arias participated on the first Disney Channel Games on the Red team. He also participated in the second Disney Channel games on the Red Team with Adrienne Bailon (Cheetah Girls). Arias was at the premiere party for The Cheetah Girls 2 which his Red team partner Adrienne Bailon starred in. Arias was a part of the Disney Channel New Year’s Sing-a-long Bowl-a-thon. He has also appeared in music videos for Pearl Jam, Jonas Brothers, and Alice in Chains.

Arias appeared in the feature film Nacho Libre opposite Jack Black in 2006.

Arias made his stage debut in the Gridirin play Water Boy at the Mark Taper Forum in Los Angeles on July 27, 2006. Water and Power was written by Arias’s Nacho Libre co-star Richard Montoya. Arias was understudied by his brother Mateo.

He was previously seen in the Jonas Brothers new music video, S.O.S. He has been acting since 2005.