This article offers an explanation for gendered patterns of work in emerging Chinese cotton spinning mills during the early twentieth century from the perspective of household labour allocation. Female workers were rarely employed in mills in the north of the country, but the Yangtze Delta showed a much higher proportion of female factory labour. Whereas many authors have explained women’s participation from the viewpoint of patriarchal culture, or physiological differences, this article brings to the fore another, largely neglected but important, explanatory factor for differences in labour allocation in modern factories during early industrialization: the development of handicraft textile production in sending regions. In districts where household cotton textile production persisted, fewer women supplied their labour to the urban factories. Landholding size, real wages, and local agricultural-industrial structures contributed to variations in the living strategies of rural households, affecting the deployment of female family members. Our argument is supported by analyses of gender wage ratios and rural–urban income disparities in different parts of China in order to expose the opportunity structures under which households decided to supply their labour to modern textile factories.