Understanding GST in India: A Complete Guide
The Goods and Services Tax (GST) replaced over a dozen indirect taxes in India when it was introduced on July 1, 2017. Whether you're a business owner, freelancer, or curious consumer, understanding how GST works is essential. This guide covers everything from the basics to input tax credit and compliance.
What Is GST?
GST is a destination-based, multi-stage, comprehensive indirect tax levied on the supply of goods and services in India. It replaced taxes like VAT, excise duty, service tax, CST, and several cesses under a single unified framework.
The key principle behind GST is that tax is collected at every stage of the supply chain, but businesses can claim credit for the GST they've already paid on inputs, so ultimately only the value addition at each stage is taxed. The final consumer bears the full tax.
Types of GST
CGST
Central GST, collected by the Central Government on intra-state supplies. Equals half the total GST rate.
SGST / UTGST
State / Union Territory GST, collected by the State Government on intra-state supplies. Also half the total rate.
IGST
Integrated GST, collected by the Central Government on inter-state supplies. Equals the full GST rate.
For example, if you sell goods at 18% GST within your state, the buyer pays 9% CGST + 9% SGST. If you sell the same goods to a buyer in another state, they pay 18% IGST.
Calculate GST Instantly
Use our free GST Calculator to compute tax-inclusive and tax-exclusive prices with CGST/SGST/IGST breakdown, cess, and a detailed invoice table.
Open GST Calculator →GST Rate Structure
GST rates in India are organized into multiple slabs based on the type of goods or services:
| Rate | Applicable To |
|---|---|
| 0% | Essential items: fresh fruits, vegetables, milk, bread, educational services, healthcare |
| 5% | Packed food items, transport services, footwear under ₹500, economy air tickets |
| 12% | Processed food, mobile phones, fertilizers, business class air tickets |
| 18% | Most goods & services: IT services, telecom, financial services, electronics, restaurants (AC) |
| 28% | Luxury & sin goods: cars, tobacco, aerated drinks, cement, premium appliances |
Additionally, precious metals like gold and silver are taxed at 3%, and rough precious stones at 0.25%. Some items also attract a compensation cess on top of the base GST rate.
Input Tax Credit (ITC)
One of the most important features of GST is the Input Tax Credit mechanism. If you're a registered business, you can claim credit for the GST you paid on your business purchases and set it off against the GST you collect on your sales.
ITC Example
You buy raw materials worth ₹1,00,000 + 18% GST = ₹18,000 GST paid. You sell finished goods worth ₹1,50,000 + 18% GST = ₹27,000 GST collected. Your net GST liability = ₹27,000 − ₹18,000 = ₹9,000. You only remit ₹9,000 to the government.
To claim ITC, you must be a registered taxpayer, the supplier must have filed their return, you must have a valid tax invoice, and the goods or services must be used for business purposes.
GST Registration: Who Needs It?
GST registration is mandatory if:
- Your annual turnover exceeds ₹40 lakh for goods (₹20 lakh for special category states)
- Your annual turnover exceeds ₹20 lakh for services (₹10 lakh for special category states)
- You make inter-state supplies
- You sell through e-commerce platforms (like Amazon, Flipkart)
- You're an e-commerce aggregator or TDS/TCS deductor
HSN and SAC Codes
Every product and service under GST is classified using a standardized code system:
- HSN (Harmonized System of Nomenclature) is used for goods. It's a globally recognized classification system.
- SAC (Services Accounting Code) is used for services. These are India-specific codes.
Businesses with turnover above ₹5 crore must mention 6-digit HSN codes on invoices. Those between ₹1.5 crore and ₹5 crore need 4-digit codes.
GST Filing and Compliance
Registered businesses must file regular GST returns:
- GSTR-1: monthly or quarterly return for outward supplies (sales), due by the 11th of the next month
- GSTR-3B: monthly or quarterly summary return with tax payment, due by the 20th of the next month
- GSTR-9: annual return, due by December 31st of the following financial year
Composition Scheme
Small businesses with turnover up to ₹1.5 crore (₹75 lakh for special states) can opt for the Composition Scheme. Under this scheme, you pay a flat rate of tax (1% for manufacturers, 5% for restaurants, 6% for service providers) without claiming ITC. You file quarterly returns instead of monthly ones.
Key Takeaways
- GST is a single, unified indirect tax that replaced 17 older taxes in India.
- There are four main rate slabs: 5%, 12%, 18%, and 28%, plus special rates for gold and precious stones.
- ITC ensures tax is only charged on value addition, not cumulatively at each stage.
- Registration is mandatory above certain turnover thresholds or for inter-state sellers.
- Small businesses can simplify compliance with the Composition Scheme.