The Fiscal Burden on Lithium: Income Tax, Export Duties, and What the RIGI Changes

A tax with three overlapping layers

The profitability of a lithium project in Argentina's Puna is not defined solely by the price of carbonate in Asia or by the operating costs of the brines. The fiscal burden is a structural variable that runs through the entire life of the deposit and is organized into three clearly differentiated levels: the provincial one, dominated by mining royalties; the national one, with income tax and export duties; and a recently created special regime, the RIGI, which alters some of these rules for large-scale investments.

Understanding how these layers interlock is essential to model a project's cash flow. Many investment analyses focus on royalties—which hover around 3% of the mine-mouth value under the Mining Investment Law—but overlook that the most significant fiscal weight tends to originate at the federal level. The complete map reveals a more demanding structure than the mere mention of royalties would suggest.

Income tax: the national anchor

Income tax is the central levy on corporate earnings. Mining companies are subject to a scheme of tiered rates, with an upper bracket around 35% for the highest profits. In lithium projects, whose capital expenditure (CAPEX) can exceed USD 500 million per plant, this tax weighs especially during the payback years, once initial investments have been amortized.

The Mining Investment Law offers relevant tools on this front, such as the 100% deduction of amounts invested in prospecting and exploration, and accelerated depreciation regimes. These advantages reduce the taxable base in the early years and improve the project's present value, though they do not eliminate the obligation but rather defer it over time.

Export duties: the most sensitive point

Export duties—known as retenciones—are perhaps the most volatile and politically sensitive fiscal component of the sector. Applied to the FOB value of lithium carbonate and chloride exports, they have fluctuated in recent years around a single digit percentage, with modifications by decree that introduced limited predictability. For a product that is almost entirely exported, such as Argentine lithium, each percentage point of export duty directly affects the project's cash flow.

The sensitivity lies in the fact that export duties are calculated on gross exported value, not on profit. This means they tax even projects with tight margins or in early production phases, when scale does not yet allow costs to be diluted. In a market with cyclical prices, this feature can compromise viability during the low points of the cycle.

What the RIGI changes

The Incentive Regime for Large Investments (RIGI), in force since 2024, was designed to attract long-term capital to strategic sectors, including mining. For projects that exceed the required investment threshold—generally hundreds of millions of dollars—the regime offers substantial benefits regarding export duties: a progressive reduction that can bring the rate to zero after a set period from start-up.

The RIGI also incorporates a reduction in the effective income tax rate and, above all, a commitment to fiscal stability for thirty years. This last point is the most valuable from the investor's perspective: it guarantees that the tax burden will not increase during the project's useful life, shielding it from future regulatory changes. In return, it demands strict access conditions and specific processing before the enforcement authority.

Fiscal stability: the intangible asset

It is worth distinguishing two stability regimes that coexist. The Mining Investment Law already offered fiscal stability for thirty years from the submission of the feasibility study, although its interpretation regarding export duties generated historical controversies. The RIGI reinforces and clarifies that shield, with more explicit rules on export duties.

For a lithium project, whose exploitation horizon can extend for decades, the certainty that the rules will not change carries a value that is hard to overstate. It reduces the country-risk premium demanded by financiers and facilitates financial closing. In economies with a history of high regulatory volatility, fiscal stability operates almost as a second-order guarantee on committed capital.

The Argentine Puna against the fiscal map

Argentina, the world's fifth-largest lithium producer, concentrates its brines in the Puna of Catamarca, Salta, and Jujuy, with operating costs among the most competitive on the planet. That geological and cost advantage coexists with a fiscal burden that, adding royalties, income tax, and export duties, may prove comparatively demanding against rival jurisdictions such as Chile or Australia.

The RIGI aims precisely to offset that gap, offering predictability to projects that might otherwise be delayed. The underlying question, for investors and the public sector alike, is whether the balance between incentives and revenue collection will manage to consolidate the Puna as a sustained investment hub. The answer will depend less on nominal rates than on the consistency with which the rules are applied over time.