Ruthie trained at Laine Theatre Arts. Following her training, she joined the UK Tour of A Chorus Line, playing Maggie. Ruthie's West End debut was in Cats, where she played a variety of roles including Jemima, Demeter, Jellylorum, Griddlebone and the leading role of Grizabella. Following Cats, Ruthie joined the world premiere cast of Miss Saigon, taking over the role of Ellen. She also played Ellen in the final Broadway company of the show, and on the acclaimed symphonic recording. In 1991, Ruthie created the role of Aphra in Children of Eden before appearances at Chichester Festival in Valentine's Day, Divorce Me, Darling and Sisterhood. Ruthie then took over as Fantine in the West End production of Les Misérables at the Palace Theatre. She was later invited to recreate this role for the acclaimed tenth anniversary concert at the Royal Albert Hall as part of the "Dream Cast", which was filmed for television. Ruthie's appearance in Crazy For You at the Prince Edward Theatre established her as one of the most popular stars in the West End. She was nominated for an Olivier Award for her performance and took the show to Canada where she played opposite Mickey Rooney. Upon her return to the West End, she took over the role of Nancy in Oliver! at the London Palladium. In 1994, Ruthie starred in She Loves Me at the Savoy Theatre, winning her first Olivier Award for Best Actress in a Musical. Ruthie starred as Roxie in the original London company of the revival of Chicago. Her performance got her nominated for her third Olivier Award, as well as being voted the 'Most Popular Musical Actress of the past 25 years' by Theatregoers. In 1999, Ruthie made her Broadway debut playing Velma Kelly, and in 2018 returned to Chicago in the West End to play Mama Morton, making Ruthie the only British actress to have played all three leading roles in Chicago. Other appearances in New York include Ziegfeld Follies of 1936 and the plays The Vagina Monologues and The Other Woman. Her appearance in Stephen Sondheim's Putting It Together, alongside Carol Burnett, was filmed for television. After three years in New York, Ruthie returned to London to star in Peggy Sue Got Married, which saw her fourth Olivier nomination. She toured the UK as the leading lady in Fosse before returning to the West End in Andrew Lloyd Webber's The Woman In White. Ruthie created the title role in Marguerite, a new musical by the creators of Les Misérables and Oscar-winner Michel Legrand, and for which she received her fifth Olivier nomination. In 2011 she appeared in Noel Coward's play Blithe Spirit as Elvira. In 2014, Ruthie joined the cast of Billy Elliot as Mrs Wilkinson at the Victoria Palace Theatre in the West End. Her performance was broadcast in cinemas around the world, with the live broadcast topping the UK and Ireland box office. In demand as a concert performer, Ruthie has toured extensively in the UK, USA and Australia. Television appearances include: Valery in The Case for BBC, Curb Your Enthusiasm, Law & Order, The Mysteries of 71st Street, The Sound of Musicals and as a judge on Dancing On Ice. Recordings including: I've Loved These Days, Pilgrim, The Ruthie Henshall Album, Love Is Here To Stay, Chicago, She Loves Me, Crazy For You, Les Misérables, The Children of Eden and I Love Musicals. Ruthie's book So You Want To Be In Musicals was released in 2012.