This paper analyses the relationship between economic growth and inequality in access to water and sanitation across 64 countries over an average period of 13.5 years. Using disaggregated data by income quintiles and rural–urban location, the study examines whether increases in GDP per capita are associated with more equitable access to essential services. The analysis combines descriptive statistics with econometric estimations (OLS, Two-Stage Least Squares, and Seemingly Unrelated Regression Equations) to assess the interaction between economic performance and inequalities in service provision.

The results show that economic growth is associated with overall improvements in access but only limited reductions in inequality. Disparities persist, particularly among lower-income groups and rural populations, while no significant relationship is found between economic growth and inequality in access to sanitation. The findings also indicate a bidirectional relationship: inequality in water access negatively affects GDP per capita. Governance effectiveness, educational attainment, and water-use efficiency emerge as more relevant predictors of equitable access than income inequality, as measured by the Gini index.

The study highlights the importance of institutional and governance factors in shaping distributive outcomes and shows that economic growth alone is insufficient to reduce inequalities in essential public services. These results contribute to debates on inequality measurement and their implications for the design and evaluation of public policies related to water and sanitation provision.