Sylvia Deaton of Lexington, Kentucky began her dance training at the Diana Evans School of Dance and as a scholarship student at the Otto M. Budig Academy of Cincinnati Ballet. In 2005, Deaton became a trainee with Boston Ballet School studying under the Sydelle Gomberg Scholarship for three years. Additionally, she attended Boston Ballet Summer Dance Program as a scholarship student for three years.
She joined Boston Ballet as a member of BBII in 2008 and as a member of the company in 2010.
Deaton's Boston Ballet repertoire includes Mikko Nissinen's The Nutcracker and Swan Lake, Peter Martins' Barber Violin Concerto, Herald Lander's Etudes, Florence Clerc's version of Petipa's La Bayadere (Manu), Maina Gielgud's Giselle (Lead Willi) and Don Quixote (Cupid), Sir Frederick Ashton's La Fille mal gardée, George Balanchine's A Midsummer Night's Dream (Lead Butterfly), Coppélia (Spinner), Divertimento No. 15 (variation #1), Ballo della Regina (soloist), Jewels, Symphony in 3 Movements, The Four Temperaments, Symphony in C (Fourth Movement demi soloist), Serenade (Russian girl), and La Valse, August Bournonville's La Sylphide, Marius Petipa's The Sleeping Beauty (Songbird, Pas de Trios, Little Red Riding Hood), John Cranko's Romeo and Juliet (clown), Jiří Kylián's Falling Angels and Symphony of Psalms, Jorma Elo's Plan to B, Sharper Side of Dark, Lost by Last, Double Evil, Carmen, and Awake Only, and William Forsythe's The Second Detail.
In 2007, Deaton competed in the Tanzolymp Festival in Berlin, Germany receiving a silver medal. She also attended an exchange program with the Royal Danish Ballet culminating in a performance of August Bournonville's Flower Festival in Genzano. Deaton attended the Festival Dance program at the Banff Centre in Alberta, Canada receiving the Alice Schultz Scholarship. She was Boston Ballet's Princess Grace nominee for 2011. Referring to 2012's Barber Violin Concerto, the Hub Review stated that Deaton "Proved a particularly appealing free spirit...grabbed her big chance with both hands...and made the biggest splash of all."