Background Previous research has identified a relationship between income inequality and child abuse and neglect in the USA. This association has received limited exploration outside the USA. Methods Administrative data on child protection (CP) in 172 English and Welsh local authorities between 2013 and 2018 were combined with data on deprivation, ethnic density and education from publicly available data sources. Commercial income data were used for Gini coefficient estimation. We tested whether similar evidence for three key findings from a US study could be found in England and Wales. These included whether there was evidence of a relationship between income inequality and child maltreatment, whether this relationship was non-linear and whether this relationship varied dependent on the level of poverty. Results There was a significant non-linear relationship between income inequality and state care rates in England and Wales. Predicted state care rates were higher as income inequality increased, up until around average levels where the effect flattens. However, there was no significant relationship for models predicting CP plan/register rates. Income inequality, income deprivation, ethnic density and higher education were able to explain around 75% of the variance in English and Welsh state care rates. Conclusions There is some evidence to support the claim of a relationship between income inequality and child maltreatment beyond the USA in England and Wales, and a case for further comparative research, but there are significant limitations in the comparability of data.