This study examines the contribution of the Goods and Services Tax (GST) to India’s overall tax revenue by comparing government collections in the pre‐ and post-GST periods. Using a descriptive and analytical research design, the study relies entirely on secondary data sourced from government budget documents, GST Council and CBIC reports, Ministry of Finance and RBI publications, and relevant scholarly work. Tools such as MS Excel were used to conduct trend analysis, comparative analysis, and percentage calculations to assess revenue patterns and identify changes following the introduction of GST. The findings reveal a substantial rise in total indirect tax revenue after GST implementation, with collections increasing from ₹7.40 lakh crore in 2017–18 to over ₹22 lakh crore in 2024–25. Major GST components—including CGST, SGST, IGST, and Cess—showed significant growth, reflecting an expanded tax base, improved compliance, and more efficient administration. Statistical evidence from the t-test confirms that the increase in revenue is highly significant and not due to random variation. Overall, the study concludes that GST has strengthened India’s tax system and enhanced revenue performance while highlighting areas for further policy improvement.