In May 1902 Ratcliffe joined the Indian English-language newspaper The Statesman as its assistant editor under Paul Knight. Later that year he met Sister Nivedita, who would become a lifelong friend. In 1903 Ratcliffe became the acting editor of The Statesman, and continued with the newspaper until 1907 when he was forced to resign for espousing Indian nationalism. Returning to London, he worked for the Daily News under A. G. Gardiner, as well as writing for the Manchester Guardian, The Spectator, the Nation and the Contemporary Review. Ratcliffe was editor of the Sociological Review from 1910 to 1917.
Ratcliffe began lecturing for the South Place Ethical Society in 1912. In 1913 he delivered a series of lectures to the League of Political Education in New York. For the next three decades he spent the winter months lecturing across the United States: “It is probable”, suggested his Manchester Guardian obituarist, “that no Englishman ever travelled so many miles in America or was heard by so many thousands of people there as he.” He also continued lecturing in England, where he became a member of the South Place Ethical Society’s panel in 1915 and in the 1930s was the society’s most regular lecturer.