APRIL 01, 2026

Tanzi Effect and India's GST

By Vijay Kumar

WHEN the Centre for Development Studies (CDS) in Thiruvananthapuram convened its international conference on the socio economic impacts of GST, the highlight was a virtual address by Professor Vito Tanzi, former Fiscal Affairs Director at the IMF. His suggestion was disarmingly simple: replace India's multi rate GST with a single uniform rate on all domestic consumption and maybe redistribute the entire revenue equally to every citizen via possibly Aadhaar linked digital transfers.

As The Hindu reported, Tanzi invoked Leonardo da Vinci's maxim- "simplicity is the ultimate form of sophistication"-as the organising principle of sound tax policy. Rather than embedding equity into a complex rate structure, he argued, India could achieve redistribution more effectively and transparently on the spending side: generate higher, stable revenue through a simplified GST, then return it directly to citizens.

Tanzi is no stranger to fiscal debates. A Harvard PhD, he directed the IMF's Fiscal Affairs Department for nearly two decades and has authored hundreds of articles and books.

His name even graces the Tanzi Effect-the erosion of tax revenue caused by inflation and collection delays.

Few economists have their names immortalised in an "Effect." Newton had his apple and Tanzi has his tax delays. His discovery was less about gravity and more about the gravity of lost revenue when governments dawdle.

Wikipedia describes Tanzi effect as:

The Tanzi effect is an economic situation involving a period of high inflation in a country which results in a decline in the volume of tax collection and a deterioration of real tax proceeds being collected by the government of that country. This is due to the time elapsed between the moment the taxable event occurs and the collection of the tax becomes effective. The effect was noticed by economists since the 1920s but it was Italian economist Vito Tanzi that explained the actual causes in a 1977 paper.

A single rate GST is not just about elegance-it is about efficiency. Multiple slabs invite disputes, lobbying, and midnight notifications. A single rate eliminates classification battles: biscuits and cakes, sarees and salwars, coconut water and cola-all taxed alike.

Imagine the relief:

- Taxpayers: no longer need to consult astrologers to divine the correct slab.

- Inspectors: no longer need magnifying glasses to decide whether a sweet is "essential" or "luxury."

- Courts: no longer need to spend years deciding whether a paratha is bread or not.

Simplification is not just fiscal-it is comic. India's GST has become a theatre of absurd classifications. Tanzi's single rate would close the curtain on this drama.

Would Tanzi's single rate work in India? Technically, yes. Politically, it is like asking India to give up cricket for kabaddi.

The Barriers to Simplicity

- Politics: Every exemption has a constituency. Try taxing sacred sweets at the same rate as SUVs-you'll hear more noise than a Diwali firecracker.

- Bureaucracy: Simplicity threatens the empire of circulars. Without complexity, how will officials justify their midnight emails?

- Lobbying: Industries thrive on special treatment. Remove slabs, and you remove bargaining chips. Expect rent seekers to protest as if you've taxed oxygen.

The Case for Simplification

Yet, simplification is the only way forward. Every slab is a loophole. Every exemption is a rent. Every delay is erosion. A single rate GST would:

- Increase revenue stability.

- Reduce litigation.

- Improve compliance.

- Restore sanity.

With one rate, India could finally retire its favourite pastime: debating whether chocolate coated biscuits are biscuits or cakes. Courts would lose a steady stream of culinary litigation, but taxpayers would gain sanity.

The Tanzi Effect is simple but devastating; when inflation is high, and tax collection is delayed, the real value of revenue shrinks. A rupee collected six months late is worth less than a rupee collected today. In India's GST regime, where compliance delays, refund backlogs, and litigation are routine, the Tanzi Effect lurks in the shadows.

Consider exporters waiting months for refunds, or small businesses grappling with portal glitches. Each delay erodes the real value of revenue, both for the exchequer and for the taxpayer. Inflation may not be galloping today, but the principle remains: inefficiency is a silent tax. Tanzi's warning is timeless-administrative delays are not neutral; they are corrosive.

The Tanzi Effect is particularly relevant to India's GST: when refunds are delayed, when compliance is bogged down in portal glitches, when litigation drags on, the real value of revenue shrinks. Inflation may be moderate, but inefficiency is corrosive. In effect, GST is not just taxing consumption-it is taxing patience.

Launched in 2017 with the promise of "One Nation, One Tax," GST quickly became "One Nation, Many Slabs." Essentials at 5%, mass consumption goods at 12%, aspirational items at 18%, luxuries at 28%, plus cesses layered on top. Each slab invites lobbying, classification disputes, and midnight notifications.

The Tanzi Effect thrives in this environment. Multiple rates mean disputes. Disputes mean delays. Delays mean erosion. The GST Council, meeting regularly, spends more time firefighting than simplifying.

Tanzi's model is radical in its elegance:

- Levy a single rate GST on all consumption.

- Redistribute the revenue equally to every citizen.

The rich, who spend more, pay more tax but receive the same transfer as the poor, who spend less. Redistribution occurs automatically, without exemptions, subsidies, or bureaucratic discretion. It is equity without complexity, fairness without forms.

India's Aadhaar, Jan Dhan accounts, and digital payments infrastructure make this technically feasible. Politically, however, every exemption has a constituency, every slab has a lobby, every complexity has a defender.

The Tanzi Effect in Indian Practice:

Examples abound:

- Exporters waiting months for refunds.

- Small businesses struggling with compliance portals.

- Midnight circulars redefining rates.

Each delay erodes value. Each complexity invites rent seeking. Each slab compromises fairness. Tanzi's warning is clear: inefficiency is not neutral-it is a hidden tax.

The CDS conference brought together academics, policymakers, and practitioners to examine GST's impacts across consumption patterns, fiscal federalism, and state finances. Tanzi's intervention cut through the jargon: simplicity is not naïve, it is sophisticated.

India's GST, in its current form, is a monument to complexity. Tanzi offers a blueprint for elegance. Whether we adopt it or not, his warning is timeless: every delay, every exemption, every slab is not just policy-it is erosion.

Professor Tanzi's reminder is timely: inefficiency is a hidden tax, complexity is a burden, and simplicity is not naïve-it is elegant. India's GST may be a monument to complexity, but the Tanzi Effect warns us that every delay erodes trust as well as revenue. Perhaps it is time to rediscover Leonardo's wisdom and let sophistication begin with simplicity.

Professor Tanzi's speech was not just a scholarly note; it was a mirror held up to India's GST experiment. His prescription reminds us that simplicity is not naïve-it is sophisticated.

Tanzi's proposal of equal per capita transfers sounds elegant in theory, but in India it would collapse under politics and perception. Citizens would ask why billionaires should get the same transfer as daily wage earners. States would demand their own tweaks, and bureaucrats would invent new forms to "verify eligibility." What begins as simplicity would quickly mutate into another labyrinth. In India, simplification is possible; redistribution, alas, is jest impossible.

One rate may be possible, but one transfer for all is jest impossible.