A seven-time Tony Award nominee, O'Hara won the 2015 Tony Award for Best Actress in a Musical for her performance as Anna Leonowens in the Lincoln Center Theater revival of "The King and I". She also received Tony nominations for her performances in "The Light in the Piazza" (2005), "The Pajama Game" (2006), "South Pacific" (2008), "Nice Work If You Can Get It" (2012), "The Bridges of Madison County" (2014), and "Kiss Me, Kate" (2019). O'Hara also received a 2019 Olivier Award nomination for her performance as Anna Leonowens in the West End revival of "The King and I".