Children are often a major beneficiary of social safety net programmes because they have higher rates of poverty. We review the evidence on whether, and to what extent, safety net spending via cash and in‐kind benefits (nutrition, early childhood education, housing and health care) affects child health and well‐being and, ultimately, children's income in adulthood. We also consider how recent changes to the safety net in the United States and the United Kingdom may affect child outcomes. We conclude that the safety net can and does help children who are growing up in poverty, with positive long‐term gains, especially among the most disadvantaged. While there is some evidence that parents may change their behaviours in response to incentives to maintain eligibility for safety net programmes, these changes appear small and, on net, children appear to be better off as a result of these programmes. A comprehensive study of the impact of the generosity and structure of the safety net on child outcomes and intergenerational mobility remains for future research.