Why was GST seen as a landmark reform in 2017?

GST replaced a fractured indirect tax system with one designed to be predictable, easy to comply with, and efficient. To see why that mattered, look at the system it replaced.

Before 2017, indirect taxes split three ways: between the Centre and the states, between goods and services, and between intra-state and inter-state trade. A supply chain could be taxed at several points, with no clean way to credit tax already paid on inputs. Earlier taxes became part of the base for later taxes. Economists call this cascading, or “tax on tax.”

Consider a box of screws worth ₹10, taxed at 10% each time it changes hands on its way into a home appliance.

Effective sales tax on a ₹10 box of screws

By the third sale, the effective tax on the original box is 33.1%, not 10%. The Tax Reforms Committee chaired by Raja Chelliah warned in 1993 that once taxes cascade through stages, the true burden on a final product becomes “almost fortuitous and largely unknown to policy makers.”

Cascading taxes cost the economy more than money changing hands. They distort decisions. A firm facing ₹13.31 in tax-inflated cost for metal screws might switch to plastic inserts priced at ₹12, even though the metal screw performs better. The tax system, not the market, made that call.

A subtler distortion ran deeper. A firm often couldn’t reclaim tax paid on a part bought from another company, so buying from a specialist carried a tax burden that making the part in-house avoided. India’s own 1994 blueprint for a VAT warned that a tax on inputs without full credit “induces vertical integration” and creates a “disincentive for specialisation in production.” Firms did more in-house, badly, instead of buying from whoever did it best. Multiply that across the economy and countless goods end up costlier or worse than they should be, a loss that never shows up on any ledger.

Exporters bore a related cost. Embedded input taxes stay embedded unless the state rebates them accurately and fast. Chelliah’s committee found that under a cascading system, calculating the right refund was “almost impossible,” turning delays and disputes into a built-in tax on exports.

GST was hailed as a landmark because it replaced this hidden, compounding tax with full input credit: producers get refunded the tax they pay on their own purchases. That is the defining feature of a Value-Added Tax, of which India’s GST is one (see “How does GST work?”). Refund the input tax and the cascade disappears, along with the distortions it caused. The promise, though, always carried a condition: the invoice-and-credit chain has to work in practice.