Implemented on 1st July, 2017, the Goods and Services Tax (GST) is considered to be the most significant Indirect Tax reform in India since independence in 1947. Positioned as a “one nation, one tax” system, GST sought to replace a complex web of cascading state and central taxes with a unified structure supported by digital compliance. Eight years since its inception, GST has demonstrated notable achievements in enhancing tax collections, broadening the taxpayer base, and promoting fiscal integration across the federation. However, the reform continues to face structural constraints, including the exclusion of petroleum products and alcoholic beverages, compliance challenges, technological infirmities, multiple tax slabs, and interpretational ambiguities. This paper critically examines GST’s performance from 2017 to 2025, highlighting both achievements and limitations, while situating reforms as imperative for the future. The analysis incorporates policy discussions, fiscal outcomes, and administrative practices. It argues that GST requires consistent rationalization, technological strengthening, and legislative simplification to realize its original promise as a comprehensive indirect tax reform for India.