"Canopus" served in the Mediterranean Fleet upon commissioning until 1903, when she was decommissioned for refitting. In 1905, she was sent to East Asia, but the renewal of the Anglo-Japanese Alliance that year rendered her presence in Asian waters unnecessary. She instead returned to Britain and served with several fleet commands in British waters, including the Atlantic Fleet, the Channel Fleet, and finally the Home Fleet. Another short deployment to the Mediterranean followed in 1908–1909. Upon returning to Britain, she was placed in reserve.