We study the effect of a key early intervention policy, designed to support families with children up to age 4, on the rate at which children up to age 9 are taken into social care. The gradual build‐up of over 3600 Sure Start Children's Centres (SSCCs), operated by Local Authorities (LAs) across England, created large spatial and cohort variation in the provision of a service that included health and parenting support, early learning and some childcare. LAs are also responsible for the safeguarding of children, and about 25 children per 10,000 are taken into care annually, in the majority of cases to protect them from abuse and neglect. SSCC provision may help to identify children at risk from maltreatment while also improving longer‐term outcomes. We therefore estimate the causal effect of SSCC provision on care entry rates, allowing separate effects for children within versus beyond the policy target age. Consistent with the hypothesized effects, our findings indicate that SSCC provision raised the care entry rate among children aged 0–4 (within target age), but reduced it for children aged 5–9 (beyond target age). We also provide corroborating evidence using data on Child Protection Plans and Serious Case Reviews.