Introduction: Dental caries and inequalities in dental health are major public health concerns. Aim: To report variation in dental caries experience across deprivation quintiles and the magnitude of inequalities between countries. Design: Secondary analyses of cross-sectional data from the 2013 Child Dental Health Survey (CDHS) in England, Wales, and Northern Ireland. Materials and methods: Distribution of dental caries across deprivation quintiles were estimated using as proportions and means. The magnitude of inequalities was calculated using the Relative Index of Inequality (RII). Main outcomes: Dental caries experience as indicated by the prevalence (%dmft/DMFT>0) and severity (dmft/DMFT) of ‘obvious’ and ‘clinical’ decay experience in both primary and permanent dentitions. Results: Children from more deprived quintiles showed higher prevalence and severity of dental caries. RIIs for dental caries were greater in England than Wales or Northern Ireland, indicating greater relative inequalities despite lower average dental caries experience. The prevalence and severity of dental caries among the most deprived children in England were 1.7 to 3.7 times greater than those of the least deprived. Conclusion: There is a deprivation gradient in child dental caries in all three countries, with England showing the greatest inequalities. Keywords: Dental Caries, Dental Health Surveys, DMF Index, Socioeconomic status