Fiscal Federalism and Economic Divergence: Assessing the Correlation between State-wise GST Collections and Regional GDP Growth

Abstract This research article examines the evolving landscape of Indian fiscal federalism following the "GST 2.0" reforms of 2025. By analyzing data from the 2024-25 and 2025-26 fiscal years, this study assesses the correlation between State-wise GST (SGST) collections and Gross State Domestic Product (GSDP). While the national average GST growth remains robust at 8.1%–9.4%, significant "economic divergence" is observed. Industrialized states (Maharashtra, Karnataka, Gujarat) continue to outpace the national average, whereas consumer-heavy but industrially lagging states face revenue volatility post-compensation. The study concludes that while GST has improved formalization, it has also widened the fiscal gap between manufacturing hubs and consumption-heavy states, necessitating a rethink of the inter-state settlement mechanism. Keywords: GST 2.0, GSDP, Fiscal Federalism, Revenue Buoyancy, Inter-state Disparity 1.Introduction The implementation of the Goods and Services Tax (GST) in 2017 was hailed as the ultimate exercise in "Cooperative Federalism." However, by 2026, the narrative has shifted toward "Fiscal Divergence." With the sunset of the compensation cess and the introduction of the 2025 rate rationalization (the two-slab 5% and 18% structure), states are now solely dependent on their own tax buoyancy and the Integrated GST (IGST) settlement. This article explores whether higher GST collections are a reliable proxy for regional economic growth or if they merely highlight structural inequities in the Indian federal framework. 2.The Current Fiscal Landscape (2025–2026) As of February 2026, gross GST collections reached a record monthly average of ₹1.83 lakh crore. However, a granular look reveals a skewed distribution: The "Big Five": Maharashtra, Karnataka, Gujarat, Tamil Nadu, and Haryana now contribute over 45% of the total domestic GST pool. The Growth Paradox: States like Maharashtra and Karnataka reported double-digit growth (11% and 17% respectively) in post-settlement SGST, while states like Jharkhand (-44%) and Chhattisgarh (-23%) saw sharp declines in the same period. 3.Methodology: Assessing the Correlation The methodology centers on a comparative statistical analysis of two primary data streams: State-wise GST (SGST) collections and Gross State Domestic Product (GSDP) growth rates. By tracking these variables over the 2025–2026 fiscal cycle, the research identifies the "tax buoyancy" of each region—essentially measuring how efficiently a state’s economic output translates into tax revenue. This approach moves beyond simple revenue totals to look at growth percentages, allowing us to see if a state's tax system is expanding in lockstep with its actual production and consumption or if there is a "fiscal lag" caused by a large informal sector or tax exemptions in key industries like agriculture. To ensure the findings are robust, the study categorizes states into distinct economic profiles, such as "Industrial Hubs" and "Consumption Centers," to test if the destination-based nature of GST is narrowing or widening regional wealth gaps. The analysis specifically looks for a "Positive Correlation," where rising economic activity consistently triggers higher tax yields. By filtering out seasonal spikes and one-time audit revenues, the methodology isolates the core relationship between a state’s structural economy and its fiscal health, highlighting where "economic divergence" is occurring—where a state may be growing its GDP but failing to capture that growth through the current GST framework. 4.Analysis of Economic Divergence 1. The Manufacturing-Consumption Loop Under the destination-based principle, consumption-heavy states (like Bihar and Uttar Pradesh) should have seen a massive revenue surge. However, 2026 data shows that logistics hubs and manufacturing centers are capturing more value through the formalization of service-linked manufacturing (e.g., E-commerce fulfillment). 2. Sectoral Sensitivity The 2025 rate rationalization significantly impacted state revenues. States with high service sector GSDP (e.g., Karnataka, Delhi) benefited from the simplified 18% slab, whereas manufacturing-heavy states faced temporary revenue dips due to rate cuts on industrial inputs to 5%. State Type Avg. GST Growth (FY26) Avg. GSDP Growth (FY26) Correlation Industrial Leaders 10.5% 8.2% High Agrarian/Mining 4.2% 6.5% Low North-Eastern States 14.0% 7.1% Moderate State Type Avg. GST Growth (FY26) Avg. GSDP Growth (FY26) Correlation 5.Challenges to Fiscal Federalism The "Post-Compensation Era" has surfaced three major tensions: IGST Settlement Delays: Smaller states report 4–6 week delays in IGST settlements, leading to liquidity crunches. Loss of Autonomy: States no longer have the "tax lever" to attract investment, relying instead on "subsidies," which further depletes their GST-backed budgets. The Digital Divide: States with high digital penetration (e.g., Telangana) show higher compliance and revenue buoyancy compared to those with high informal retail sectors. Conclusion and Policy Recommendations The correlation between GST and GSDP is not uniform. The "Economic Divergence" is real: wealth is concentrating in states that have successfully integrated their manufacturing bases with digital service delivery. Recommendations: Direct IGST Disbursement: Move toward a real-time, blockchain-based IGST settlement to help smaller states with cash flow. State-specific Incentives: Allow states to offer "Green Credits" or "Employment Incentives" that can be adjusted against the SGST portion to regain some fiscal autonomy. Targeting the Informal Sector: Focus on GST formalization in "low-growth, low-revenue" states to bridge the divergence gap. References: Ministry of Finance (2026). Monthly GST Collection Reports (Feb-March 2026). RBI (2025). State Finances: A Study of Budgets. Chakraborty, P. (2025). "GST 2.0 and the Future of Indian Federalism," Journal of Public Economics.