Tveit has also portrayed several musical theatre roles on screen, such as Enjolras in the film adaptation of Les Misérables (2012), as well as Danny Zuko in Fox's Grease: Live (2016).

Tveit is also known for his work in television, including the roles of Gareth Ritter on BrainDead, Tripp van der Bilt on Gossip Girl, Mike Warren on Graceland, and Danny Bailey/Topher in Schmigadoon!.

[14] In the following two years, he performed in regional productions including as Matt in Barrington Stage Company's Calvin Berger in July 2007 and as D'Artagnan in a musical adaptation of The Three Musketeers which played at the North Shore Music Theatre from August to September 2007, before returning to the Broadway production of Hairspray.

[20] In the interim time before the out-of-town production of Next to Normal, Tveit played Dean in the musical theatre adaptation of the film Saved!, which ran for a limited engagement at Playwrights Horizons in June 2008.

[29][30] In August, he also starred in the Hollywood Bowl's production of Rent directed by Neil Patrick Harris, as Roger Davis.

[32][33] Tveit played Frank Abagnale Jr in the Broadway production of Catch Me If You Can, opening on April 10, 2011, and closing on September 4, 2011.

[37] During the Broadway production of Next to Normal, Tveit also had a recurring role in the CW series Gossip Girl as Tripp van der Bilt, the cousin of Nate Archibald.

[39] He appeared in Rob Epstein's Howl, a biopic about the Allen Ginsberg poem and the controversy and trial that ensued after its publication.

[41] In 2012, Tveit played Enjolras, leader of the student revolutionary group in the film adaptation of Les Misérables.

He 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.

[44] The following year, he starred in the USA Network series Graceland where he played undercover FBI Special Agent Mike Warren.

[45] Between filming seasons of Graceland, Tveit starred and made his London stage debut in the Menier Chocolate Factory's production of Stephen Sondheim's Assassins as John Wilkes Booth.

[48] During this time he also began performing solo concerts and recorded his own album The Radio in My Head[49] as well as the concept album for a new Broadway show An American Victory: A New Musical in January 2014 with Ashley Brown, Hugh Panaro, Ruthie Henshall, Alexander Gemignani, and many other Broadway stars.

[50] Additionally, he appeared in the film Big Sky which was released on August 14, 2015[51] and performed at the first Elsie Fest in New York that September.

[61][62] He next had a role in the Patricia Clarkson-starring crime thriller Out of Blue, which premiered at the 2018 Toronto International Film Festival.

[63] In November 2017, Tveit participated in a developmental lab for the stage adaptation of the 2001 movie Moulin Rouge!, cast in the role as Christian, the character originally created by Ewan McGregor.

[66] Between the Boston and Broadway productions of Moulin Rouge!, Tveit had a recurring role as the aspiring politician Matt Dobbins on the 2019 CBS show The Code.

[79] Released in April 2021, Tveit was a cast member of Hit Job, a scripted comedy podcast produced by Lorne Michaels' Broadway Video for Audible.

[85] On February 9, 2024, Tveit replaced Nicholas Christopher in the Broadway revival of Sweeney Todd: The Demon Barber of Fleet Street in the title role.