GST Structure

The Goods and Services Tax (GST) is a comprehensive, multi-stage, destination-based indirect tax levied on the “supply” of goods and services. It replaced a fragmented network of central and state indirect taxes to establish a unified common national market.

Shift from Origin to Destination-Based Taxation

Unlike the legacy tax structure which operated on an origin-based principle (where tax accrued to the state where production occurred), GST is a destination-based consumption tax. The revenue is collected by and accrues to the jurisdiction where the goods or services are ultimately consumed.

Multi-Stage Value Addition and the Mitigation of Cascading Effects

GST is levied at every node of the supply chain from raw material procurement to final retail sale. It operates strictly on the principle of value addition. The cascading effect (“tax on tax”) is systematically mitigated through the Input Tax Credit (ITC) mechanism, which allows businesses to deduct the tax already paid on inputs from the tax liability due on their final output.

The Dual GST Model

To preserve the fiscal autonomy of India’s federal structure, a concurrent Dual GST model was adopted. Under this framework, both the Central Government and State Governments simultaneously levy tax on a common base:

• Central GST (CGST): Levied by the Centre on intra-state supplies of goods and services.
• State GST (SGST) / Union Territory GST (UTGST): Levied by States and Union Territories with legislatures (and UTGST by UTs without legislatures) on intra-state supplies.
• Integrated GST (IGST): Levied and collected by the Central Government on all inter-state supplies of goods and services, as well as on imports. The IGST revenue is subsequently apportioned between the Centre and the consuming State based on statutory formulas.

Constitutional Foundations and Institutional Governance

The implementation of GST required sweeping constitutional amendments to redefine the taxing powers of the Union Parliament and State Legislatures.

The 101st Constitutional Amendment Act, 2016

This landmark amendment introduced critical constitutional articles to facilitate the transition to the concurrent taxation regime:

• Article 246A: Grants simultaneous legislative power to both Parliament and State Legislative Assemblies to make laws with respect to goods and services tax imposed by the Union or by such State. Crucially, Parliament retains exclusive power to legislate on GST where the supply of goods or services takes place in the course of inter-state trade or commerce.
• Article 269A: Mandates that GST on inter-state transactions (IGST) shall be levied and collected by the Government of India and apportioned between the Union and the States on the recommendations of the GST Council. It also explicitly clarifies that the import of goods or services is treated as an inter-state supply, subjecting imports to IGST alongside basic customs duties.
• Article 279A: Empowers the President of India to constitute the GST Council, a joint institutional forum of the Centre and the States to oversee and regulate the entire tax architecture.

The Voting and Decision-Making Matrix of the GST Council

The GST Council embodies the principles of cooperative federalism. To ensure that neither the Centre nor the States can make arbitrary modifications to the tax structure, decisions require a three-fourths (75%) majority of the members present and voting. The institutional voting power is explicitly weighted as follows:

Evolution to GST 2.0: The Rationalized Structural Slabs

Following extensive structural reforms initiated during the 56th GST Council meeting, the legacy multi-tier structure (consisting of 0%, 5%, 12%, 18%, and 28% slabs) was phased out. The current regime, designated as GST 2.0, collapsed the intermediate 12% and high 28% slabs to form a simplified three-tier primary rate framework alongside a strict list of fully exempted items. This structural shift eliminated rate ambiguities, minimized classification disputes, and lowered daily household and compliance costs.

The Simplified Three-Tier Slab and Exempt Category Matrix

Special Niche Tax Rates

To preserve tracking and formalization without imposing punitive financial burdens on high-value, low-volume industries, a few specialized low rates continue to operate:

• 0.25% Rate: Applied uniformly to rough, unsorted precious stones, diamonds, and semi-precious blocks.
• 3.0% Rate: Applied directly to the final transaction value of precious metals including gold, silver, platinum, and fine jewelry.

Indirect Taxes Subsumed vs. Outside the Purview of GST

To build a unified national market, a multitude of distinct central and state levies were permanently dissolved into the GST framework. However, certain high-yield revenue items were explicitly excluded to preserve structural emergency fiscal buffers.

Indirect Taxes Subsumed into GST

• Central Levies: Central Excise Duty; Additional Duties of Excise; Service Tax; Countervailing Duty (CVD) or Additional Duty of Customs; Special Additional Duty of Customs (SAD); Central surcharges and cesses related to the supply of goods and services.
• State Levies: State VAT / Sales Tax; Central Sales Tax (levied by the Centre but collected by origin states); Luxury Tax; Entry Tax and Octroi; Entertainment Tax (except those levied by local municipal bodies); Taxes on advertisements; Taxes on lotteries, betting, and gambling; State cesses and surcharges.

Commodities Excluded from the Purview of GST

• Alcohol for Human Consumption: Completely excluded from GST via constitutional definition. States retain exclusive legislative rights to levy State Excise Duties on manufacturing and localized VAT/Sales Tax on retail distribution.
• Five Specified Petroleum Products: Petroleum crude, high-speed diesel, motor spirit (petrol), natural gas, and aviation turbine fuel (ATF) remain temporarily outside GST. They continue to attract Central Excise Duty and State VAT until the GST Council recommends their formal inclusion.
• Electricity Duties: Taxes on the consumption or sale of electricity remain under the legislative control of individual State Governments.

Key Structural Mechanisms, Terms, and UPSC Prelims Trivia

Reverse Charge Mechanism (RCM)

Typically, the supplier of goods or services deposits the tax with the government. Under RCM, this statutory liability is reversed: the recipient of the goods or services is legally mandated to calculate and pay the GST directly to the exchequer. RCM is deployed when sourcing goods or services from unorganized suppliers or specific designated sectors.

Inverted Duty Structure Correction

An inverted duty structure occurs when the tax rate on raw materials or input components is significantly higher than the tax rate on the final finished product. This creates an uncompetitive domestic manufacturing environment and forces firms to accumulate unused Input Tax Credits. Under the structural pillars of GST 2.0, the CBIC corrected this distortion by aligning output rates (such as dropping output apparel rates or adjusting man-made fiber inputs from 18% to 5%) to promote domestic value addition.

Anti-Profiteering Mechanism

To ensure that businesses pass on the economic benefits of GST rate reductions or expanded ITCs to consumers via proportional price cuts, the law contains structural anti-profiteering clauses. These compliance checks are monitored and enforced by designated competition regulatory cells.

Input Service Distributor (ISD) Alignment

An Input Service Distributor is a business office that receives tax invoices for services utilized by its distinct branches or manufacturing plants. The ISD pools these invoices and systematically distributes the corresponding CGST, SGST, or IGST credits to its operational units using standardized revenue allocation keys.

Composition Scheme

A simplified compliance pathway designed for small taxpayers whose annual aggregate turnover does not cross a specified statutory threshold (typically Rs. 1.5 Crore for manufacturers and traders). Eligible businesses pay a nominal, flat tax rate (such as 1% or 5%) directly on their quarterly turnover and are legally barred from issuing taxable tax invoices, collecting GST from customers, or claiming any Input Tax Credit.