Cassidy McAndrew began her ballet training at age five in Stamford, CT. At eleven, she continued her training at Ballet Academy East (BAE) under the direction of Darla Hoover. Upon graduating from BAE in 2015, Cassidy joined Charlotte Ballet as an apprentice for the 2015–2016 season, where she was mentored by the legendary Patricia McBride.

She subsequently danced with Philadelphia Ballet for four seasons, performing corps de ballet and soloist roles in a wide-ranging repertoire by Angel Corella, Jerome Robbins, George Balanchine, Ben Stevenson, Sir Kenneth MacMillan, Alexander Ekman, Matthew Neenan, and Helen Pickett.

In 2021, Cassidy joined Los Angeles Ballet for the 2021–2022 season. From 2022–2025, she freelanced throughout the greater Los Angeles area, performing principal roles with companies including Inland Pacific Ballet, Ballet Project OC, and The Realm Company.

Cassidy began teaching in 2020 and has taught at notable institutions such as Ballet Academy East, Los Angeles Ballet School, Westside School of Ballet, and Inland Pacific Ballet. Now based in Bozeman, she is thrilled to join MBC as a member of the Company and a faculty member, sharing her artistry, experience, and love of ballet with the greater Bozeman community.