This study aimed to describe the health status of children and how social deprivation affects their use of healthcare services and mortality. Children living in mainland France were selected from the national health data system (SNDS) on their date of birth or birthday in 2018 (< 18 years) and followed for one year. Information included data on healthcare reimbursements, long-term chronic diseases (LTDs) eligible for 100% reimbursement, geographic deprivation index (FDep) by quintile (Q5 most disadvantaged), and individual complementary universal insurance (CMUc) status, granted to households with an annual income below the French poverty level. The number of children who had at least one annual visit or hospital admission was compared using the ratio of geographic deprivation (rQ5/Q1) and CMUc (rCMUc/Not) after gender and age-standardization. Over 13 million children were included; 17.5% had CMUc, with an increase across quintiles (rQ5/Q1 = 3.5) and 4.0% a LTD (rQ5/Q1 = 1.44). The 10 most frequent LTDs (6 psychiatric) were more common as the deprivation increased. Visits to general practitioners (GPs) were similar (≈84%) for each FDep quintile and the density of GPs similar. The density decreased with increasing deprivation for specialists and visits: paediatricians (rQ5/Q1 = 0.46) and psychiatrists (rQ5/Q1 = 0.26). Dentist visits also decreased (rQ5/Q1 = 0.86) and deprived children were more often hospitalised for dental caries (rQ5/Q1 = 2.17, 2.1% vs 0.7%). Emergency department (ED) visits increased with deprivation (rCMUc/Not = 1.35, 30% vs 22%) but 50% of CMUc children lived in a municipality with an ED vs. 25% without. Approximately 9% of children were admitted for a short stay and 4.5% for a stay > 1 night (rQ5/Q1 = 1.44). Psychiatric hospitalization was more frequent for children with CMUc (rCMUc/Not = 3.5, 0.7% vs 0.2%). Higher mortality was observed for deprived children < 18 years (rQ5/Q1 = 1.59). Our results show a lower use of pediatricians, other specialists, and dentists among deprived children that may be due, in part, to an insufficient supply of care in their area of residence. These results have been used to recommend optimization and specifically adapted individual or area-wide policies on the use of healthcare services, their density, and activities.