Before appearing on Broadway, Whitehead was a Rockette in Los Angeles and New York at the start of her career right out of high school. She toured and performed in Fosse, The Will Rogers Follies, All Shook Up and Paul McCartney's "Driving Rain" tour. Her Broadway debut was starring in the 2006 Broadway revival of A Chorus Line, in which she played the character of Kristine alongside Tony Yazbeck. The audition process that she took to get the role can be seen in Every Little Step, a documentary of the A Chorus Line Broadway revival casting process. Following Broadway, television roles ensued, as well as the musicals Damn Yankees as Lola, Gigi, Cats, A Chorus Line (as Cassie) and Will Rogers Follies as Z's Favorite. In 2011, she appeared in the role of Kathy opposite Neal Patrick Harris as Bobby in the New York Philharmonic production of Company. In 2016- 2017, she played the role of Kitty in the Broadway revival of Chicago, where she understudied and performed the role of Velma Kelly.

On television, Whitehead appeared as Helen Boyd in a 2007 episode of Grey's Anatomy, "Kung Fu Fighting", as well as in the TV series In Plain Sight in the episode "Coma Chameleon", playing the character of Krista. In 2011, she appeared on the TV series Castle, The Mentalist and Happy Endings. In 2012, she appeared on Switched at Birth. In 2013, she had a recurring role on four episodes of Private Practice. In 2014, Whitehead was a recurring guest star for three of the six final episodes of Warehouse 13. She played Claire Donovan, the older sister and eldest sibling to Claudia and Joshua Donovan. Her last television appearance was during the second season of Grimm in 2014.