The Unified Tax Architecture: Overview of GST in India

Introduced on July 1, 2017, the Goods and Services Tax (GST) replaced a fragmented web of cascading central and state indirect taxes—including Central Excise Duty, Service Tax, State VAT, Entry Tax, and Octroi. GST operates as a destination-based, multi-stage consumption tax levied at every point of value addition.

The Four Principal Tax Components

  • CGST (Central Goods and Services Tax): Collected by the Central Government on intra-state transactions (sales where buyer and seller are within the same state).
  • SGST (State Goods and Services Tax): Collected by the State Government on intra-state transactions.
  • UTGST (Union Territory GST): Levied in place of SGST in Union Territories without a legislature (e.g., Andaman and Nicobar Islands, Chandigarh).
  • IGST (Integrated GST): Levied on all inter-state supplies (when goods cross state borders) and import transactions, administered by the Centre.

For example, if an electronic accessory carries an 18% GST rate and is sold within Uttar Pradesh, the tax is split into 9% CGST + 9% SGST. If sold from Maharashtra to Karnataka, a single 18% IGST is applied.

The 5 Core GST Slabs and Applicable Goods

  1. 0% (Exempted): Fresh agricultural produce, unpacked grains, milk, eggs, salt, curd, and essential educational services.
  2. 5%: Packaged basic food items, tea, coffee, edible oil, life-saving medicines, and domestic air travel.
  3. 12%: Processed foods, business computers, mobile phones, processed dairy items, and basic apparel above set price points.
  4. 18% (Standard Rate): The most widely applied slab—capital goods, software utilities, consumer electronics, banking services, and retail accessories.
  5. 28% (Luxury & Sin Goods): High-end automobiles, motorcycles above 350cc, air conditioners, aerated drinks, and tobacco products (often accompanied by an additional Compensation Cess).

What Is an HSN Code and Why Is It Mandatory?

HSN (Harmonized System of Nomenclature) is an international 6-digit classification code developed by the World Customs Organization (WCO). In India, it is expanded to 8 digits for detailed domestic tax tracking:

  • Businesses with annual turnover up to ₹5 Crores are required to list a minimum 4-digit HSN code on B2B invoices.
  • Businesses with annual turnover exceeding ₹5 Crores must report a 6-digit HSN code on all B2B and export invoices.
  • SAC (Services Accounting Code): The equivalent coding system used specifically for classifying service industries.

Composition Scheme vs. Regular Scheme: Which Should You Choose?

Small traders with turnover up to ₹1.5 Crores can opt for the Composition Scheme. Under composition, the merchant pays a flat nominal tax (e.g., 1% of turnover for traders) and files simplified quarterly returns. However, composition dealers cannot issue tax invoices to pass Input Tax Credit (ITC) to their buyers, making the Regular scheme preferable for businesses dealing with corporate or wholesale clients.

Frequently Asked Questions

Can I calculate GST backwards from an MRP price (Reverse GST)?

Yes. If a product's final retail price inclusive of 18% GST is ₹1,180, the taxable base price is calculated using the formula: $Base = rac{Total}{1 + (Rate / 100)} = rac{1180}{1.18} = ₹1,000$. The tax amount is ₹180.

Is GST registration mandatory for all small shops in India?

Under current regulations, registration is generally mandatory for goods businesses with annual aggregate turnover exceeding ₹40 Lakhs (₹20 Lakhs in northeastern and hill states), and for service providers exceeding ₹20 Lakhs. Inter-state online e-commerce sellers are generally required to register regardless of turnover.