Understanding India’s Dual GST Structure
India follows a constitutional Dual GST Model introduced under Article 246A of the Constitution of India. Because India is a federal democracy with distinct taxing powers distributed between the Union Government and the State Governments, both governments possess concurrent jurisdiction to tax supplies of goods and services.
To implement this dual structure without creating double taxation or tax cascading, the Goods and Services Tax framework divides all indirect taxation into four specific components:
Master Comparison: CGST vs SGST vs IGST
Here is an exhaustive, point-by-point legal comparison outlining how CGST, SGST, and IGST differ in applicability, administration, revenue sharing, and tax credit rules:
| Feature | CGST | SGST | IGST |
|---|---|---|---|
| Full Form | Central Goods & Services Tax | State Goods & Services Tax | Integrated Goods & Services Tax |
| Governing Statute | CGST Act, 2017 | Respective SGST Acts, 2017 (e.g. Maharashtra SGST Act) | IGST Act, 2017 |
| Type of Supply | Intra-State (Same state) | Intra-State (Same state) | Inter-State (Across states, SEZ, Imports) |
| Levied & Collected By | Central Government | State Government | Central Government |
| Revenue Destination | Retained by Centre | Retained by State where goods/services consumed | Shared 50:50 between Centre and Consuming State (Art. 269A) |
| Rate Proportion | 50% of total GST rate (e.g. 9% of 18%) | 50% of total GST rate (e.g. 9% of 18%) | 100% of total GST rate (e.g. 18%) |
| Applicable Partner Tax | Always accompanied by SGST or UTGST | Always accompanied by CGST | Charged standalone (single tax line) |
| ITC Set-Off Priority | 1st against CGST, 2nd against IGST (never SGST) | 1st against SGST, 2nd against IGST (never CGST) | 1st against IGST, 2nd against CGST or SGST in any order |
| Cross-Utilization | PROHIBITED with SGST | PROHIBITED with CGST | PERMITTED with both CGST & SGST |
| Transaction Example | Supplier in Mumbai → Buyer in Pune (9% CGST) | Supplier in Mumbai → Buyer in Pune (9% SGST) | Supplier in Mumbai → Buyer in Bengaluru (18% IGST) |
Intra-State vs Inter-State: How to Determine Applicable Tax
The choice between charging CGST + SGST or IGST depends strictly on the legal determination of two parameters under the IGST Act, 2017:
- Location of the Supplier: The registered place of business or establishment from where the supplier makes the supply.
- Place of Supply (POS): The statutory destination where goods are delivered or services are performed (governed by Sections 10, 11, 12, and 13 of the IGST Act).
1. Intra-State Supply (Section 8 IGST Act)
When the Location of the Supplier and the Place of Supply are in the SAME State or Union Territory:
Example: A computer retailer in Ahmedabad sells a laptop to a customer in Surat. Both are in Gujarat. If the GST rate is 18%, invoice shows 9% CGST + 9% SGST.
2. Inter-State Supply (Section 7 IGST Act)
When the Location of the Supplier and the Place of Supply are in DIFFERENT States or Union Territories:
Example: An IT company in Noida (Uttar Pradesh) provides consulting services to a client in Delhi. The invoice shows full 18% IGST.
Interactive GST Component Calculator
Test any invoice amount to see exactly how CGST, SGST, and IGST get split across standard Indian GST tax slabs:
Live Intra-State vs Inter-State Tax Simulator
Select your transaction type, taxable base amount, and GST rate to see the live statutory tax breakdown.
Input Tax Credit (ITC) Utilization Order: Rule 88A
One of the most critical aspects of GST accounting is how input tax credits are offset against output tax liabilities. The Central Board of Indirect Taxes and Customs (CBIC) introduced Rule 88A and amended Section 49 of the CGST Act to establish a strict sequence of credit set-off.
Step 1: Exhaust IGST Credit Completely First
You must completely exhaust your available IGST Input Tax Credit before you are allowed to touch any CGST or SGST credits. IGST credit is first used to offset IGST output liability. Any remaining IGST balance can be used to pay CGST and SGST output liabilities in any proportion or order chosen by the taxpayer.
Mandatory: IGST Input Balance must reach ₹0 before next stepStep 2: Utilize CGST Credit
Once IGST credit is fully exhausted, CGST Input Tax Credit is applied first against CGST output liability. Any surplus CGST credit can then be used to pay IGST liability. CGST credit can NEVER be used to pay SGST liability.
CGST → CGST first, then IGSTStep 3: Utilize SGST / UTGST Credit
Similarly, SGST Input Tax Credit is applied first against SGST output liability. Any surplus SGST credit can then be used to pay IGST liability. SGST credit can NEVER be used to pay CGST liability.
SGST → SGST first, then IGSTInvoicing Best Practices: Rule 46 Compliance
When generating an invoice under Rule 46 of the CGST Rules, 2017, suppliers must ensure the correct tax columns are explicitly stated. Incorrect tax head reporting can lead to ITC denial for your business customers:
- Separate Columns on Invoice: For intra-state sales, never combine CGST and SGST into a single “GST 18%” row. The invoice must clearly print the taxable value, the CGST rate and rupee amount, and the SGST rate and rupee amount in separate columns.
- State Code & Place of Supply: The buyer’s 2-digit GST state code and name must be prominently stated whenever the supply is inter-state, or whenever an intra-state supply to an unregistered buyer exceeds ₹50,000.
- B2B Recipient GSTIN: For your buyer to claim ITC, ensure their 15-digit GSTIN is valid and verified using a GSTIN Validator.
For a detailed breakdown of all 16 mandatory legal fields required on a tax invoice, read our dedicated GST Invoice Format 2026 Legal Guide.