BACKGROUND: Information on variation in the recording of child maltreatment in administrative healthcare data can help to improve recognition and ensure that services are able to respond appropriately. OBJECTIVE: To examine variation in the recording of child maltreatment and related diagnoses. DESIGN: Cross-sectional analyses of administrative healthcare records (Hospital Episode Statistics). SETTING AND PARTICIPANTS: Acute injury admissions to the National Health Service in England of children under 5 years of age (1997-2009). Outcome measure Annual incidence of admission for injury recorded by International Classifications of Diseases 10 codes for maltreatment syndrome (child abuse or neglect) or maltreatment-related features (assault, undetermined cause or adverse social circumstances). Proportion of all admissions for injury coded for maltreatment syndrome or maltreatment-related features. RESULTS: From 1997 to 2009, the annual incidence of injury admissions coded for maltreatment syndrome declined in infants and in 1-3-year-old children while admissions coded for maltreatment-related features increased in all age groups. The combined incidence of these categories remained stable. Overall, 2.6% of injury admissions in infants, and 0.4-0.6% in older age groups, had maltreatment syndrome recorded. This prevalence more than doubled when maltreatment-related codes were added (6.4% in infants, 1.5-2.1% in older age groups). CONCLUSION: Despite a shift from maltreatment syndrome to codes for maltreatment-related features, the overall burden has remained stable. In combination, the cluster of codes related to maltreatment identify children likely to meet thresholds for suspecting or considering maltreatment and taking further action, as recommended in recent National Institute of Health and Clinical Excellence guidance, and indicate a considerable burden to which hospitals should respond.