Tveit made his Broadway in 2006 as Link Larkin in the musical Hairspray, having previously played the role in the national tour. Following his success in Hairspray, he went on to originate the roles of Gabe in Next to Normal and Frank Abagnale, Jr. in Catch Me If You Can. Other significant roles include Fiyero in Wicked on Broadway, Dean in the Off-Broadway musical Saved, D'Artagnan in the musical The Three Musketeers at North Shore Music Theatre and Roger in Rent at the Hollywood Bowl.
On television, Tveit played the recurring character William "Tripp" van der Bilt III on "Gossip Girl," and is currently starring as Mike Warren on "Graceland." On film, he recently appeared as Enjolras in the musical "Les Misérables."