In this paper, we analyze one of the early welfare interventions in the Swedish welfare state targeted towards mothers and young children: the introduction of a child day-care system. Because quantitative research on day-cares in historical settings is generally scarce, in this study, we focus on the determinants of day-care enrollment in southern Sweden during the early twentieth century. We use unique longitudinal micro-level data for the city of Landskrona obtained from the Scanian Economic Demographic Database, which has been linked to individual-level records of day-care attendance for children born between1900 and 1935. Event-history techniques are employed to analyze the importance of factors such as household composition, parental socio-economic background, marital status of the mother, and mother’s occupation. Of the studied children, 8 percent were ever enrolled in daycares, most of them around the ages 3 to 6. The results show that the mother’s marital status, household SES, the presence of other adult females in the household and mother’s occupation are all significant determinants of day-care attendance for children. In this study, we show that day-care attendance followed a negative SES gradient and was most common among children of single mothers, in the early twentieth century in southern Sweden