Butler began his career on television, first in roles on Disney Channel and Nickelodeon, most notably on Zoey 101 (2007–2008), and later on teen dramas, including recurring parts on The CW's Life Unexpected (2010–2011) and Switched at Birth (2011–2012).

Butler made his Broadway debut in the 2018 revival of The Iceman Cometh and portrayed Tex Watson in Quentin Tarantino's film Once Upon a Time in Hollywood (2019).

[1] He has since starred as Gale Cleven in the war drama miniseries Masters of the Air (2024) and Feyd-Rautha Harkonnen in the science fiction film Dune: Part Two (2024).

[7] He has an older sister, Ashley (born in 1986), who worked as a background actress alongside him on Ned's Declassified School Survival Guide.

[5][8] His maternal great-great-grandparents, Matti Matinpoika Sillanpää and Liisa Jaakontytär Järvelä, were Finnish immigrants from Ostrobothnia, Finland, who settled in Wisconsin.

[9][10] When Butler was thirteen, he was approached by a representative from a background acting management company at the Orange County Fair who helped him get started in the entertainment industry.

In 2005, after working as an extra on several television series, including Unfabulous and Drake & Josh, Butler landed his first regular job as a background actor playing the role of Zippy Brewster for two seasons on Nickelodeon's Ned's Declassified School Survival Guide.

[4][5][13] In February 2010, Butler landed a recurring role as Jones on the CW series Life Unexpected,[4][12][14] Later that year, he guest-starred in episodes of the Disney Channel sitcoms Wizards of Waverly Place and Jonas as well as on CSI: Miami and The Defenders.

[17][18] In the same year, he signed on to play the lead role of Zack Garvey in the Lifetime television film The Bling Ring, made by Dick Clark Productions and directed by Michael Lembeck, based on the burglary group of the same name who targeted the homes of Hollywood's celebrities.

[20] In his early twenties, Butler continued to act in teen-oriented television series, but gained greater recognition for his starring roles in The Carrie Diaries and later The Shannara Chronicles; he also branched out into new stage and film projects.

He played the role of Bradley, a pre-law student with a double major in political science and math, and is set to graduate from a wealthy university.

[30] Butler made his Broadway debut playing Don Parritt, the "lost boy" in The Iceman Cometh, which starred Denzel Washington and David Morse.

Per Hilton Als's review of the play in The New Yorker: "Although there are many performers in George C. Wolfe's staging of Eugene O'Neill's phenomenal [...] drama, The Iceman Cometh, [...] there is only one actor, and his name is Austin Butler.

"[31] In 2019, Butler appeared in the Quentin Tarantino film Once Upon a Time in Hollywood as a fictional version of Manson Family member Tex Watson.