Tveit also starred in the CBS series Brain Dead as Gareth Ritter.where he was active both in theater and sports, playing golf, soccer and basketball while also performing in all four of his school's theater productions. He turned down business school scholarships to major in vocal performance at Ithaca College, a decision his parents supported, before switching to musical theater after his freshman year because he missed acting and theater.In January 2014, he recorded the concept album for a new Broadway show An American Victory: A New Musical with Ashley Brown, Hugh Panaro, Ruthie Henshall, Alexander Gemignani, and many other Broadway stars.The cast recording was released more than two years later in April 2016.In July 2012, Aaron Tveit took part in a private reading for a new musical based on the animated film, Anastasia.Tveit read for the character Dimitri, a con man who brings Anastasia to a wealthy Empress searching for her missing granddaughter, in return for a reward.Also in June 2008, Tveit began performances as Fiyero in Wicked.He left the role in November in order to reprise his role in the Arena Stage production of Next to Normal, for which he was awarded the 2009 Helen Hayes Award for Outstanding Supporting Performer in a Non-Resident Production.
In November of that year, Tveit participated in a developmental lab for the stage-adaption of the 2001 movie Moulin Rogue!
, cast in the role as Christian, the character originally created by Ewan Mc Gregor.
Tveit appeared in Rob Epstein's Howl, a biopic about the Allen Ginsberg poem and the controversy and trial that ensued after its publication.
In September 2013, Broadway Records released The Radio in My Head, a live recording of songs Tveit performed at New York City venue 54 Below.
Some of the songs on the album are from musicals in which Tveit has starred, including "I'm Alive" from Next to Normal, "Goodbye" from Catch Me If You Can, and "One Song Glory" from Rent.