The Goods and Services Tax (GST), implemented on July 1, 2017, marked a transformative shift in India's indirect taxation system. Designed to consolidate a plethora of central and state taxes into a unified tax structure, GST aimed to enhance transparency, reduce tax evasion, and simplify the tax compliance process. This study investigates the impact of GST on the revenue of the state of Rajasthan, a region with a diverse economy that includes agriculture, mining, tourism, and small-scale manufacturing. The research evaluates the trends in tax revenue before and after the introduction of GST, with a focus on components such as the State Goods and Services Tax (SGST), Integrated Goods and Services Tax (IGST), and Central Goods and Services Tax (CGST). Additionally, it highlights the influence of national economic policies, settlement delays, and the phasing out of compensation from the central government on the state’s revenue structure. The paper also addresses the challenges posed by high VAT rates on fuel, leading to cross-border fuel purchases, and the declining share of non-tax revenues. Through an analysis of official data, government reports, and comparative performance with other Indian states, the study provides a comprehensive understanding of how GST has shaped Rajasthan’s fiscal trajectory. The paper concludes with a set of policy recommendations aimed at strengthening the state’s revenue generation mechanisms, ensuring fiscal sustainability, and optimizing the benefits of GST implementation.