Charles Albert Watts took over the radical publishing house, Watts & Co, founded by John and Charles Watts in 1864, when his parents emigrated to Canada in 1883.
He began the journal Watts's Literary Guide in November 1885. In the first issue, which sold for one penny, the anonymous editor set out his ambition to fill it with "literary gossip" of interest to freethinkers, together with recording "the best liberal publications in this country". It also contained details of his father's speaking tours of Canada and the US, and regular criticisms of the Christian establishment on every front, from science and metaphysics to history and poetry. The name was changed to The Literary Guide in 1894, and continued after his death, becoming The Humanist, and later still The New Humanist.
Charles Albert Watts, together with other figures like F. J. Gould and Joseph McCabe, also organised the Propagandist Press Committee, which later became the Rationalist Press Association, in 1899, with G. J. Holyoake as first President. This was founded to "assist in securing the amendment of the law which sanctions the confiscation of property left for anti-theological purpose, and to promote the issuing, advertising, and circulation of publications devoted to Freethought and Advanced Religious reform." (Blasphemy Depot, p. 6). This resulted in a larger group of subscribers, and enabled him to expand the magazine in size and with a widening readership.
Throughout his long life Charles Albert Watts remained out of the limelight. He was described as "...decisive but self-effacing. He encouraged controversy in his pages, though he shrank from it himself." He did not allow his own name to appear in the magazine until his sixtieth birthday, in 1918. He edited the journal for over 60 years until his death, writing editorial content himself and drawing on contributors from a wide range of disciplines, including Annie Besant, Walt Whitman, and H. G. Wells.
He also expanded the work of his business, Watts & Co., into publishing books, including a series of "cheap reprints" which made the works of such writers as Charles Darwin, Thomas Huxley and John Stuart Mill available to a mass audience, at only sixpence a volume. This later became the "Thinker's Library", a series of 140 small books published between 1929 and 1951. They included essays, literature, and extracts from works by various classical and contemporary humanists and rationalists.