The Goods and Services Tax (GST) marked a transformative shift in India’s indirect taxation by replacing a fragmented system with a single, unified framework aimed at efficiency and transparency. However, this consolidation also absorbed several environmental levies, raising critical questions about the continuity of eco-taxation for sustainable development. This study examines the constitutional, fiscal, and policy aspects of integrating environmental taxes within India’s GST regime. It analyses relevant judicial interpretations and explores technological tools—particularly artificial intelligence and blockchain that can foster modernization of eco-tax governance and its implementation. It envisions evolution of GST as a tool for maintaining the balance between environmental taxation and economic growth of the country ceaselessly. Finally, it proposes the concept of an “E-GST” mechanism that balances ecological sustainability with fiscal stability. The findings emphasize that a sustainable taxation represents not a deviation, but a natural evolution toward a resilient and environmentally responsible India