What Is GST? A Plain-English Guide for Indian Businesses
GST — Goods and Services Tax — is India's unified indirect tax on almost every product and service bought or sold in the country. It replaced a confusing web of 17 different central and state taxes when it launched on 1 July 2017.
- GST is a single, destination-based indirect tax that replaced 17 central and state taxes from 1 July 2017.
- It is collected at every stage of the supply chain, but businesses claim Input Tax Credit (ITC) so tax is paid only on value added.
- India uses four types of GST — CGST, SGST, IGST, and UTGST — depending on whether a sale is intra-state or inter-state.
- GST registration is mandatory above ₹40 lakh turnover for goods or ₹20 lakh for services (₹20 lakh / ₹10 lakh in special category states).
- Every registered business gets a 15-digit GSTIN that must appear on all tax invoices.
- Goods and services fall into six rate slabs: 0%, 3%, 5%, 12%, 18%, and 28%.
India's tax system before GST was, frankly, a mess. Businesses had to navigate VAT, service tax, excise duty, octroi, and several other levies — each with its own filing system, rate structure, and compliance requirement. GST's "One Nation, One Tax" framework was one of the most significant economic reforms in independent India's history.
What Does GST Stand For — and What Does It Tax?
GST stands for Goods and Services Tax. It is a destination-based, multi-stage indirect tax — collected at every stage of the supply chain where value is added, and ultimately borne by the final consumer.
GST applies to virtually all goods and services in India. However, certain items are exempt or zero-rated. Specifically, fresh fruits and vegetables, milk, eggs, and educational services attract zero GST. Electricity, petrol, diesel, alcohol, and real estate operate under separate state-level tax regimes.
What did GST replace?
State taxes absorbed: VAT/Sales Tax, Entry Tax, Luxury Tax, Octroi, State Excise (on manufactured goods), Entertainment Tax, Advertisement Tax.
How GST Works — The Multi-Stage Tax Explained
GST is collected at every stage of the supply chain, from manufacturer to retailer to consumer. Businesses at each stage can claim a credit for the GST they already paid on their inputs — this is called Input Tax Credit (ITC). The tax is effectively paid only on the value added at each stage.
Manufacturer sells goods worth ₹1,000 + 18% GST (₹180) to wholesaler. Pays ₹180 to government.
Wholesaler adds ₹200 value, sells for ₹1,200 + 18% GST (₹216). Claims ₹180 ITC. Pays only ₹36 net.
Retailer adds ₹300 value, sells for ₹1,500 + 18% GST (₹270). Claims ₹216 ITC. Pays only ₹54 net.
Consumer pays ₹1,770 total. Total GST collected = ₹270 — only on final value.
The Four Types of GST in India
For intra-state transactions, GST splits equally between CGST and SGST. An 18% GST becomes 9% CGST plus 9% SGST. For inter-state transactions, only IGST at the full rate applies.
Who Needs to Register for GST?
GST registration is mandatory once a business crosses the annual turnover threshold. Businesses with turnover above ₹40 lakhs (for goods) or ₹20 lakhs (for services) must register. Businesses in special category states have a lower threshold of ₹20 lakhs for goods and ₹10 lakhs for services.
Certain businesses must register regardless of turnover: inter-state suppliers, e-commerce operators and their sellers, businesses under reverse charge mechanism, and anyone supplying through an e-commerce aggregator.
What is a GSTIN?
Upon registration, every business receives a GSTIN — Goods and Services Tax Identification Number. It is a 15-digit alphanumeric code: 2-digit state code + 10-digit PAN + 1-digit entity number + 1-digit check digit. The GSTIN must appear on every tax invoice.
GST Rate Slabs — The Quick Reference
For a complete breakdown of which products fall under each slab, read our detailed guide on GST rate slabs in India 2024. To understand how CGST and IGST differ in actual transactions, see our article on CGST vs SGST vs IGST.
GST is not merely a tax reform. It is an economic union of states. — Arun Jaitley, Finance Minister, at the GST launch ceremony, 30 June 2017
Official GST Portal — Government of India
CBIC — Central Board of Indirect Taxes and Customs
GST Basics — Frequently Asked Questions
When did GST come into effect in India?
GST was launched on 1 July 2017, replacing 17 different central and state indirect taxes including VAT, service tax, excise duty, and octroi.
What is the difference between CGST, SGST, and IGST?
CGST and SGST apply equally on intra-state transactions (collected by the central and state governments respectively), while IGST applies as a single tax on inter-state transactions and is collected by the central government.
Who must register for GST?
Businesses with annual turnover above ₹40 lakhs (goods) or ₹20 lakhs (services) must register, along with all inter-state suppliers, e-commerce sellers, and businesses under reverse charge, regardless of turnover.
What is a GSTIN?
A GSTIN is a 15-digit alphanumeric Goods and Services Tax Identification Number issued on registration, made up of a 2-digit state code, 10-digit PAN, an entity number, and a check digit.
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