Tax collection before and after GST looks like two different systems built on different assumptions. Before July 2017, indirect tax in India was a stack of separate levies collected by separate authorities at separate points in the supply chain, with credits that rarely flowed across those boundaries. After GST, a single tax attaches to a single event called “supply,” runs on a shared digital platform, and lets businesses offset tax paid on inputs against tax owed on sales across the whole country. The revenue also moves differently: it now flows to the state where goods and services are consumed rather than where they are made.
How Collection Worked Before GST
The pre-2017 system layered central and state taxes on top of each other, each with its own triggering event and its own paperwork.
At the central level, the Central Excise Act of 1944 taxed goods at the point of manufacture. Section 3 of that Act imposed the Central Value Added Tax (CENVAT) on excisable goods produced in India, and other provisions governed the physical removal of those goods from the factory.1India Code. The Central Excise Act, 1944 Services were taxed separately under the Finance Act of 1994, administered by the Central Board of Excise and Customs.2Department of Revenue. Service Tax
At the state level, every state ran its own Value Added Tax with its own rates, exemptions, and returns. A business selling into several states registered in each one and complied with each set of rules independently. Entry tax, octroi, and luxury tax sat on top of that in various places. And all of it operated on an origin-based principle: the state that produced or first sold the goods kept the revenue, whether or not the buyer lived there.
The Cascading Tax Problem
The most damaging feature of that structure was that taxes stacked on top of each other. Central excise and state VAT were administered by different authorities, and credit earned under one could not offset liability under the other. A manufacturer who paid excise on raw materials could not use that credit against state VAT on the finished product. Each successive tax was calculated on a base that already included prior taxes.
The arithmetic was straightforward. A wholesaler pays ₹10 tax on a ₹100 purchase and sells the goods on for ₹110. The retailer then pays tax on ₹110, including on the ₹10 of tax already embedded in the price. The final consumer pays the full compounded amount without ever seeing it broken out. Removing that cascade was the specific problem GST was designed to solve.
What GST Changed at the Structural Level
The Constitution (One Hundred and First Amendment) Act of 2016 gave both Parliament and state legislatures the power to levy GST, and the framework that emerged has three parts.3Goods and Services Tax Council. The Constitution (One Hundred and First Amendment) Act, 2016
- Central GST (CGST), collected by the central government on sales within a state.
- State GST (SGST), collected by the state government on the same intra-state sale, at the same rate as CGST.
- Integrated GST (IGST), collected by the central government on inter-state sales, imports, and exports, then apportioned to the consuming state.4PRS Legislative Research. Issues for Consideration – The Goods and Services Tax Bills, 2017
A product taxed at 18% within a state carries 9% CGST and 9% SGST. If the same sale crosses a state border, IGST applies at the full 18% and the destination state receives its share. Both levels of government collect from every transaction without the buyer or seller navigating separate regimes.
One Taxable Event Instead of Several
Under the old rules, different taxes were triggered by different events. Excise attached when goods left the factory. Service tax attached when a service was rendered. VAT attached at the point of sale. GST collapsed those triggers into a single concept.
Section 7 of the CGST Act defines supply broadly to cover sale, transfer, barter, exchange, licence, rental, lease, or disposal of goods or services made for consideration in the course of business. It also covers imported services and certain transactions without consideration, such as stock transfers between branches in different states. Most commercial activity now falls inside one definition rather than being sorted across three or four separate statutes.
Destination Rather Than Origin
Because excise attached at manufacture, manufacturing-heavy states collected more than consumption-heavy states under the old system. GST reversed that. Revenue now goes to the state where goods or services are consumed, and the IGST Act sets out detailed place-of-supply rules to make the routing work.5Central Board of Indirect Taxes and Customs. The Integrated Goods and Services Tax Act, 2017 For goods that move, the place of supply is where the movement ends. For services supplied to a registered business, it is the recipient’s location. For imported goods, it is the importer’s location.
How Rates Are Set Now
GST rates are organised into slabs of 0%, 5%, 12%, 18%, and 28%, with a compensation cess on some luxury and demerit items on top of the highest slab. Which items sit in which slab is decided not by individual states or by the central Finance Ministry acting alone, but by the GST Council, a constitutional body established under Article 279A. The Council includes the Union Finance Minister as chair and the finance minister of every state.6Goods and Services Tax Council. GST Council
This is a real change in how rate decisions are made. Before GST, each state legislature could set VAT rates on its own, and competitive rate-cutting to attract businesses eroded tax bases across the country. Now rate changes go through a shared body rather than 29 independent ones.
Who Has to Register
Section 22 of the CGST Act requires a supplier to register once aggregate turnover in a financial year crosses ₹20 lakh. For special category states, mainly in the northeast and hill regions, the threshold is ₹10 lakh. Later notifications raised the threshold to ₹40 lakh for suppliers dealing exclusively in goods in most states, while services stay at ₹20 lakh.7Central Board of Indirect Taxes and Customs. Central Goods and Services Tax Act 2017 – Section 22 Some categories, including inter-state suppliers and e-commerce operators, must register regardless of turnover.
Small businesses that would find full compliance heavy can opt into the composition scheme, which charges a flat percentage of turnover: 1% for traders, 2% for manufacturers, 5% for restaurants.8Central Board of Indirect Taxes and Customs. Frequently Asked Questions on Composition Levy The trade-off is that composition dealers cannot collect tax from buyers, cannot claim input tax credit, and cannot make inter-state sales.
Input Tax Credit: The Mechanism That Removes the Cascade
The single most important operational change in how tax is collected is input tax credit. Under Section 16 of the CGST Act, a registered buyer can claim credit for the GST paid on purchases and set it off against GST owed on sales. To do so, the buyer needs a valid tax invoice from a registered supplier, the supplier must have reported that sale in their return, and the tax must actually have reached the government.9Central Board of Indirect Taxes and Customs. CGST Act 2017 – Section 16
Two rules keep the chain honest. If goods against a single invoice arrive in instalments, credit is available only after the last instalment. If the buyer does not pay the supplier within 180 days of the invoice date, the credit already claimed is reversed and interest is owed. Every buyer therefore has a direct financial stake in the compliance of its own suppliers, which is what makes the anti-cascade mechanism work in practice.
Not everything qualifies. Section 17(5) blocks credit permanently on certain categories regardless of business use, including most passenger motor vehicles, food and beverages, personal care and wellness services, works contracts and materials for constructing immovable property on one’s own account, club memberships, and employee travel benefits, with narrow carve-outs where the input is central to the business itself.10Central Board of Indirect Taxes and Customs. CGST Act 2017 – Section 17(5) Plant and machinery used in construction is a notable exception on the credit side even when the building itself is not.
Reverse Charge
Normally the seller collects GST and deposits it. Under the reverse charge mechanism, that obligation flips to the buyer. It applies in two main situations: purchases by registered businesses from unregistered suppliers, and specific notified categories.11GST Council. Reverse Charge Mechanism Notified services include legal services from individual advocates, goods transport agency services, sponsorship services, and any service imported from outside India. On the goods side, agricultural commodities like raw cotton, tobacco leaves, and cashew nuts purchased directly from farmers fall under reverse charge. In each case the larger registered buyer, not the smaller informal supplier, is left to handle the compliance.
The Digital Backbone
Collection now runs on a single national platform. The Goods and Services Tax Network (GSTN) handles registration, return filing, and payment processing for every registered taxpayer in the country.12Goods and Services Tax Network. About Us The paper ledgers and manual returns of the old regime are gone, replaced by transaction-level data that flows into government systems in near real-time.
Two enforcement tools depend on this backbone. The first is the e-way bill: any consignment of goods worth more than ₹50,000 must carry an electronic waybill generated through the portal before it moves, and officers can check it in transit.13Central Board of Indirect Taxes and Customs. CGST Rules – Rule 138 The second is automated invoice matching. Invoices that a seller reports in its outward supply return are cross-checked against the credits its buyers claim. Mismatches are flagged and the buyer’s credit is restricted until resolved. This matching is what turns input tax credit from a paper right into an enforceable one.
Interest and Penalties Under the New Regime
Missing a payment deadline triggers interest under Section 50 of the CGST Act at up to 18% per annum on the unpaid amount, running from the day after the due date until payment.14Central Board of Indirect Taxes and Customs. CGST Act 2017 – Section 50 Where a business claimed and used input tax credit it was not entitled to, the rate rises to 24% per annum. Interest is generally calculated on the net cash liability, but on the gross liability in cases involving fraud or deliberate evasion.
Section 132 creates tiered criminal penalties for tax evasion, wrongful credit, or fraudulent refunds.15Central Board of Indirect Taxes and Customs. CGST Act 2017 – Section 132 Amounts over ₹5 crore attract imprisonment up to five years plus fine. Amounts of ₹2 crore to ₹5 crore attract up to three years. Amounts of ₹1 crore to ₹2 crore attract up to one year, for specified offenses. Repeat offenders face up to five years regardless of amount, and courts are directed to impose a minimum sentence of six months unless they record special reasons. Administratively, the GST Council has set the threshold for launching prosecution at ₹2 crore, which focuses enforcement on larger fraud rather than smaller compliance errors.
The Short Version of What Changed
Before GST, indirect tax collection was several parallel systems: excise on manufacture, service tax on services, VAT and other levies at the state level, each with its own trigger, its own authority, and no shared credit. Tax stacked on tax, and manufacturing states kept the revenue.
After GST, one tax attaches to one event called supply, splits between the centre and the state on intra-state sales, and moves through IGST on inter-state ones. Credit flows across the whole chain if suppliers actually pay what they collect, and a national digital platform matches invoices to enforce that condition. Revenue follows consumption rather than production. Rates come from a shared council rather than independent legislatures. The forms are different, but so is almost everything upstream of the forms.