This report provides new information on the costs of delayed disclosures of CSA (child sexual abuse) on the NHS in England and Wales. The costing indicates that the highest costs were accrued before disclosure, supporting the finding that delayed disclosure leads to higher costs to the NHS and to CSA survivors. Average lifetime health cost per CSA survivor was estimated to be £4.9m, while the total lifetime health-related economic burden was estimated to be 2.9b. One implication of these findings is that interventions provided by the NHS are an important part of the overall response. Recommendations include better preparing NHS staff to recognise and manage disclosures effectively and utilise trauma-informed models, and additionally that more investment is needed in identifying and preventing CSA on the same scale as the efforts involved in tackling domestic abuse.