Global minimum tax: OECD prepares first economic assessment of Pillar Two

On 15 July 2026, the OECD published a new assessment of the economic consequences of the global minimum tax. Based on updated modelling and the first data available for fiscal year 2024, this study concludes that effective tax rates have increased, profit transfers have decreased and corporate tax revenues have increased.

The first results also show no statistically significant negative effects on investment or employment. However, these conclusions must be interpreted with caution: the implementation of the scheme remains recent and its economic effects may only be gradually apparent.

Global minimum tax: a change in tax paradigm

From Pillar Two of the OECD/G20 project, the global minimum tax aims to ensure a minimum effective taxation of 15% of the profits made in each jurisdiction by multinational groups within its scope.

In principle, the scheme concerns groups with consolidated turnover of at least EUR 750 million. Its operation is based on several complementary rules allowing additional tax to be levied where the effective tax rate calculated in a court is less than 15%.

The objective is twofold: to limit profit transfer strategies to low-tax jurisdictions and to reduce the interest of States in competition based exclusively on lower corporate tax rates.

The evaluation published in July 2026 is an important step. It no longer relies solely on projections prior to the entry into force of the scheme, but incorporates updated information on its implementation and the first financial data after 2024 (OECD, World Minimum Tax Economic Impact Assessment, 2026).

A significant increase in effective tax rates

According to OECD estimates, the global minimum tax is expected to lead to an average increase in effective tax rates between 2.8 and 3.7 percentage points at the court level.

The effect would be even greater in « Investment centres », where the expected increase would be between 5.5 and 6.9 points.

These results reflect the logic of Pillar Two. The nominal corporate tax rate of a state is no longer sufficient to assess a group's tax exposure. The calculation is based on an effective rate determined by jurisdiction, based on specific accounting and tax rules.

Tax benefits, exemptions and tax credits should therefore be reviewed in the GloBE calculation (Global Anti-Base Erosion). An attractive tax system under domestic law may lose some of its interest if it leads to the application of a supplementary tax in the jurisdiction concerned or in another jurisdiction of the group.

Expected reduction in profit transfers

The OECD estimates that the global minimum tax could reduce international transfers of profits between 22.6% and 44.6%.

The magnitude of this estimate shows that the exact effect remains uncertain. However, it reflects a structural change: when the tax gap between two jurisdictions decreases, the tax gain that may result from shifting profits is also reduced.

The study thus anticipates a decrease from 19% to 25% in effective tax rate differences between jurisdictions. This convergence could promote a more economic-based allocation of capital — access to markets, infrastructure, skills or legal certainty — only on the tax differential.

For international groups, this development does not make transfer pricing policies less important. On the contrary, the combination of GloBE rules, documentary obligations and controls over profit allocation requires greater consistency between the location of functions, assets, risks and results.

Additional income for States

The OECD estimates the annual increase in corporate tax revenues between 3.2% and 5.4% compared to a scenario where the global minimum tax would not have been applied in any jurisdiction.

These additional revenues could come from several mechanisms:

• the collection of a national minimum tax qualified by the States in which the weakly taxed entities are established;
• the application of supplementary tax by the court of the parent entity;
• the reduction of artificial transfers of profits;
• the amendment of national tax systems in order to preserve the taxable material locally.

This last consequence is decisive. States have an interest in collecting supplementary tax themselves rather than letting another court apprehend. Pillar Two could thus lead to a gradual restructuring of preferential regimes and national policies.

Tax competition does not disappear. It moves towards instruments compatible with the new framework: subsidies, infrastructure, targeted public expenditure, refundable tax credits or schemes based on substantial economic activity.

No measurable negative effects on investment or employment at this stage

The OECD also reviewed the consolidated financial statements of multinational groups for the financial year 2024. Preliminary data show that firms falling within the global minimum tax scope have experienced an increase in their effective tax rate compared to those not covered.

On the other hand, the analysis shows no statistically significant declines in investment or employment among the groups concerned for the first year.

This result is important, but it does not yet lead to a definitive conclusion that there is no economic impact. A year is a short observation period. Decisions on establishment, restructuring or investment are generally based on a longer horizon. Transitional regimes and the still uneven implementation of Pillar Two may also delay some effects.

The OECD itself states that the expected consequences could take time to materialize and that they will continue to be assessed as new data become available.

What practical consequences for international groups?

For the companies concerned, the issue now exceeds the calculation of any additional tax. Pillar Two must be integrated into the group's overall tax governance.

Several points require special vigilance:

• the reliability of the accounting data used to calculate the effective rate in each jurisdiction ;
• The link between GloBE rules, national minimum taxes and local legislation;
• treatment of tax credits, deficits, deferred taxes and temporary differences;
• eligibility for protection schemes and transitional measures;
• consistency between the results of Pillar Two, transfer pricing documentation and country-by-country declarations;
• The impact of the scheme on restructuring, acquisitions and location choice.

Groups that are not immediately liable for additional taxes are not necessarily immune from any difficulties. The collection of data, the justification of calculations and the traceability of the positions chosen alone represent a significant burden of compliance.

A first validation, but not a final assessment

The new OECD study tends to confirm that the global minimum tax has the desired effects: increased effective taxation, narrowing the gap between jurisdictions, limiting transfers of profits and increasing government revenues.

It also provides an initial response to investment and employment concerns, without revealing significant negative effects at this stage.

However, this is only a first assessment. The data focus on the first year of implementation, while its deployment remains heterogeneous and groups such as States are still adapting their behaviour.

The global minimum tax thus opens a new phase of international taxation: that of observing its real effects. For multinational groups, Pillar Two is no longer just a compliance project. It becomes a sustainable parameter of the international fiscal, financial and operational strategy.