[10] In 2008, Altomare joined the first national touring cast of the Broadway musical Spring Awakening in the lead role of Wendla, beginning previews on August 15, 2008, in San Diego.

Seth Kubersky of Orlando Weekly called her "appropriately innocent and adorable as the inevitable victim"[12] while Eric Rezsnyak of the Rochester City Paper praised her "piercing, haunting soprano voice," and how "even her most difficult melodic passes seem totally effortless.

"[13] Following the Spring Awakening tour, Altomare appeared as Sue Snell in MCC Theater's limited-engagement run of the Off-Broadway revival of Carrie at the Lucille Lortel Theatre.

On March 9, 2016, it was announced that Altomare would star in the world premiere of the musical adaptation of the 1997 animated film Anastasia in the title role (nicknamed Anya).

[21] Altomare played Nellie in a concert version of South Pacific at the Aspen Music Festival on July 22, 2019.

[22] Since the closing of Anastasia, Altomare has performed frequently in the Broadway Princess Party concert both in New York City and occasionally touring in selected cities across North America alongside fellow original Broadway princesses Laura Osnes, Susan Egan, Courtney Reed, and more.

[23][24] On January 16, 2020, it was announced that Altomare would star in the new musical The Wanderer as Susan alongside Wicked alums Michael Wartella as Dion DiMucci and Joey McIntyre as Johnny, running May 28 through June 28 at Paper Mill Playhouse prior to a Broadway transfer.

[26] In February 2021, Altomare announced that she would release a solo album of original music, titled Wandering Bird, later that year.

[28] Altomare was cast in the role of Scarlet in the world premier of "Noir" on the Hubbard Stage of the Alley Theatre in Houston, Texas.