This article uses population censuses to provide the first consistent counts of the population of business proprietors for 1891–1911. After appropriate adjustments for imperfect Census design the article confirms the persistence of own account self-employed as the most common businesses throughout the period. However, it identifies a turning point around 1901 when the business numbers decisively shifted towards larger firms, where employers with waged workers began substituting for many own account businesses. Developments were, however, multi-faceted, with important sector differences, and some fields of female business beginning to take off over the period, especially in retail and the professions.