Ella Barrier was hired in 1875 to teach in the segregated schools of Washington, D.C. She stayed in Washington for more than forty years, working as a teacher, school principal, and clubwoman. Barrier helped develop the Washington branch of the YWCA. In 1891, she taught in Toronto, as part of a teacher exchange project. In 1900 she and her sister traveled as African-American representatives at the Paris Exposition, and to the First Pan-African Conference in London, in a delegation that included Anna Julia Cooper and W. E. B. DuBois. She was active in the Colored Women's League in Washington.