In this study, building a simple model that incorporates static and dynamic elements, the relationship of financial development and economic growth to environmental degradation is investigated together with the validation of the Environmental Kuznets Curve (EKC) hypothesis. Our analysis is based on an unbalanced panel data set covering the OECD countries over the period 1970–2014. Our approach thoroughly accounts for the presence of cross‐sectional dependence between the sample variables and utilizes second generation panel unit root tests in order to investigate possible cointegration relationships. The empirical findings do indicate that local (NOx per capita emissions) and global (CO2 per capita emissions) pollutants redefine the EKC hypothesis when we account for the presence of financial development indicators. Specifically, in the case of global pollution an N‐shape relationship is evident in both static and dynamic frameworks, with a very slow adjustment. Lastly, our study calls for a strengthening of the effectiveness of environmental degradation policies by ensuring sustainability of the OECD banking system in order to drastically reduce emissions. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment