[10] In September 1894, Truax made her professional stage debut with Otis Skinner's Chicago-based stock company playing Lady Castlemaine in Clyde Fitch's His Grace de Grammont.

[11] On April 18, 1897, at St. John's Episcopal Church, Truax married Guy Bates Post, at the time a fellow cast member with Skinner's company performing at San Francisco's Baldwin Theatre.

[16] By April 1898 Truax was a member of the Great Northern Stock Company playing Virginia, the daughter of Frederick Warde's title rôle, Virginius, by Sheridan Knowles.

[17] Later in the year Truax was engaged as a leading lady at the Bastable Theatre, Syracuse, where that September she played Mercedes in Charles Fletcher's adaptation of Alexandre Dumas' The Count of Monte Cristo and, in April 1899, Mrs. Arbuthnot in Oscar Wilde's A Woman of No Importance.

[24] In the fall of 1903, Truax embarked on a tour with the Hall Caine drama The Eternal City, in which she played Donna Roma Volonna to the David Rossi of Edward J. Morgan and Baron Bonelli of Frederic De Belleville.

[28][29] In 1905, Truax toured in Hall Caine’s The Christian, playing Gloria Quayle, and on February 5, 1906, at Chicago's Colonial Theatre, she created the rôle Princess Irene in John I. C. Clarke's adaptation of the Lew Wallace historical novel The Prince of India.

[32] Truax had left the cast of The Prince of India by the time of its Broadway debut in September 1906, appearing that December instead at the old Bijou Theatre as Anna Hartmann in Mary Roberts Rinehart's drama The Double Life.

She was Lady Olivia in the modest success The Man Who Ate the Popomack, a dramatic comedy by Walter J. Turner that made its debut at the Cherry Lane Theatre on March 24, 1924.

[41][42] On June 30, 1913, she began a six-week engagement at Pittsburgh's Grand Opera House performing the title rôle in Charles Hale Hoyt's farce-comedy A Contented Woman.

[43] Beginning that fall and on into the spring of 1914 she was Domini Enfilden to Lawson Butt's Boris Androvsky in road productions of The Garden of Allah, a play by Mary Anderson based on the book by Robert Smythe Hichens.

[44][45] Truax again played Domini in The Garden of Allah in an extended tour that began in the fall of 1916 and ended in March 1918 after closing out a near four-week run at Broadway's Manhattan Opera House.