AbstractInformal childcare care by grandparents, other relatives or friends is an important source of support in many Western countries, including Germany. Yet the role of this type of care is often overlooked in accounts of social policies supporting families with children, which tend to focus on formal childcare. This article examines whether the large formal childcare expansion occurring in Germany in the last two decades has been accompanied by similar or opposite trends in informal childcare usage. It argues that accounting for both formal and informal childcare can offer a more accurate assessment of defamilisation effects of family policies. Drawing on representative data from the German Socio‐Economic Panel the analysis identifies long‐run developments of childcare arrangements for children aged 1–10 between 1997 and 2020, offering for the first time a comprehensive picture of how families with children of different ages mix informal care and service provision. Results show that on average the expansion of formal childcare was not associated with an equal reduction in informal childcare, lending little support to the crowding‐out hypothesis. Further analyses distinguishing between population groups with different propensity to use formal childcare reveal, unexpectedly, remarkable similarities in the use of informal care throughout the period examined. The only exception are families with a migrant background, who tend to use informal childcare less than their counterparts. The general trend is, however, one whereby informal and formal care are increasingly combined.