Environmental sustainability has become a major concern for policymakers across the globe. In this regard, understanding the factors responsible for environmental degradation is particularly important for developing nations. Against this backdrop, this study aims to evaluate the impacts of environmental regulations and other vital macroeconomic aggregates on the ecological footprints in the context of four fossil fuel-dependent South Asian countries: Bangladesh, India, Pakistan, and Sri Lanka. The major findings from the econometric analysis, accounting for cross-sectional dependency, slope heterogeneity, and structural break issues in the data, reveal that environmental regulations portray significant roles in directly and indirectly reducing the ecological footprints across South Asia. Besides, the elasticity estimates verify the authenticity of the environmental Kuznets curve and the pollution haven hypotheses. On the other hand, non-renewable and renewable energy consumptions are found to increase and decrease the ecological footprints, respectively. Moreover, renewable energy use and environmental regulations are found to jointly reduce the ecological footprints further. More importantly, environmental regulations are predicted to reduce the adverse environmental impacts of economic growth, non-renewable energy use, and foreign direct investment inflows while increasing the favorable environmental impacts associated with renewable energy use. Furthermore, the country-specific impacts of environmental regulations on the ecological footprints are found to be more or less homogeneous to the corresponding panel estimates. The environmental Kuznets curve and pollution haven hypotheses are evidenced to hold for the majority of the four South Asia nations. In line with these findings, several relevant policy-level suggestions are put forward.