Comparative child welfare administrative data from each of the four jurisdictions of the UK (Scotland, England, Northern Ireland (NI) and Wales) were analysed over a ten-year period to examine rates and patterns of public care. Scotland followed by Wales has the highest rates of children in out-of-home care, followed by England and NI with similar lower proportions. Despite strong links between deprivation and higher chances of becoming looked after, this national variation appears more a reflection of differing legal and operational practice than higher levels of need for public care. Notwithstanding differing devolution settlements, a convergence in the direction of policy across the UK towards early intervention, extensive use of kinship care and adoption as an exit route from public care is apparent. This convergence is most apparent in the increased entry of very young children to public care in Scotland, NI and Wales. The lack of any systematic collection of data by governments on the social and economic conditions of children reflects a missed opportunity to examine separately their influence on rates of children in public care.