PRESS STATEMENT
Country-Level Revenue Estimates – A Comparative Analysis of UN and OECD Subject to Tax Rules for 65 Member States of the G-24 and South Centre
Washington and Geneva, 23 July 2025
The South Centre & Group of Twenty-four today jointly released country-level revenue estimates of the UN & OECD Subject to Tax Rule (STTR) for their 65 combined Member States.
Results show higher revenues from UN STTR, and reinforce benefits of a UN Tax Convention.
Comparison of Tax Revenue Effects of United Nations and OECD Subject to Tax Rule for G-24 and South Centre Member States
By Faith Amaro and Sol Picciotto
The Subject to Tax Rule (STTR) seeks to address the historical imbalance in the allocation of taxing rights under international tax treaties by introducing within existing treaties a new article which makes the restrictions on source taxation conditional on the residence jurisdiction imposing a minimum level of tax on foreign-derived income. This paper presents a methodology for analysing the respective benefits of the STTRs developed by the Organisation of Economic Co-operation and Development (OECD) and the United Nations (UN). Applying this model to publicly available data for 2021, it also provides estimates of the possible revenue impact for the 65 Member States of the South Centre (SC) and the Intergovernmental Group of 24 (G-24). Our analysis indicates that the OECD STTR would have no impact on any OECD country treaty with a SC/G-24 Member State. Applying the prescribed 9% minimum rate to covered payments, only 100 treaties across 28 SC/G-24 Member States would qualify for improvement under the OECD STTR, with an estimated combined revenue gain of USD 55.6 million, 71% of which is concentrated in just five treaties. In contrast, the UN STTR, which does not specify a minimum rate, was modelled using rates of 9%, 10% and 15%. This resulted in estimated revenue gains of USD 212 million, USD 325 million, and USD 1,165 million across 171, 210 and 317 treaties, respectively. Given its complexity and restrictive scope, it seems pointless for any SC/G-24 Member State to join the OECD STTR. Instead, countries should focus on identifying treaties that cause unjustifiable revenue losses and consider revising them – either by adopting the simpler and broader UN STTR or implementing other measures such as active anti-abuse provisions to combat treaty shopping and tax avoidance.
Analysing the Impact of UN and OECD Subject to Tax Rule for G-24 and South Centre Member States
By Suranjali Tandon and Chetan Rao
The Subject to Tax Rule (STTR) is meant to address base erosion and profit shifting in cross –border transactions. The United Nations (UN) and Organisation for Economic Co-operation and Development (OECD)/Group of Twenty (G20) Inclusive Framework have developed models of the STTR that countries may choose to adopt in their treaties. This paper provides a review of these designs of two STTR models and proceeds to estimate the revenue gains for the Intergovernmental Group of Twenty-Four on International Monetary Affairs and Development (G-24) and South Centre Member States that may arise from a STTR that covers different kinds of payments. The OECD STTR is limited to related-party payments and imposes thresholds based on mark-up and materiality, reducing its applicability in practice. In contrast, the UN STTR offers broader coverage, applies to both related and unrelated parties, and does not impose restrictive thresholds, making it more administratively feasible for developing countries. Although the estimated gains from the OECD STTR appear modest due to its narrow scope, the UN STTR shows greater potential. The analysis also highlights data limitations and the need for access to microdata for accurate country-level assessments.
Status of Permanent Establishments under GloBE Rules
By Kuldeep Sharma
The objective of this Research Paper is to comprehensively identify and analyse all Permanent Establishment (PE) related provisions under the global minimum tax of the Organisation for Economic Co-operation and Development (OECD), which is implemented through the Global Anti Base Erosion (GloBE) Model Rules. The analysis has led to the conclusion that PEs hold a significant position and facilitate application of GloBE Rules.
The GloBE Rules have introduced certain new facets involving application of PE provisions when there is no tax treaty; no Corporate Income Tax (CIT) in the source state, and have brought in the concept of stateless PEs. These newly-introduced facets have widened the scope of PEs to enable application of the GloBE Rules in specific situations which would otherwise have remained outside the ambit of taxation.
The paper concludes with an observation that the OECD’s Inclusive Framework is drafting the provisions of Amount A in a manner that results in consistency with GloBE Rules. Likewise, acceptance of “deemed PE” for GloBE rules should be extended to Amount A as well. By doing so, a tax nexus would be provided in source jurisdictions, which will allow profits attributable to Multinational Enterprises (MNEs) in a digitalized economy (without physical presence) getting taxed under domestic rules of these source (market) jurisdictions. This would have been a much simpler solution and would have eliminated the complexity of Amount A rules to a large extent, as we see today.
Beyond the Two Pillar Proposals
A Simplified Approach for Taxing Multinationals
By Sol Picciotto, Muhammad Ashfaq Ahmed, Alex Cobham, Rasmi Ranjan Das, Emmanuel Eze, Bob Michel
This paper puts forward an alternative to the proposed multilateral convention under Pillar One of the BEPS project, by building on and going beyond the progress made so far. A new direction was signalled in 2019 by the G-24 paper proposing a taxable nexus based on significant economic presence, combined with fractional apportionment. The resulting measures agreed under the two Pillars entail acceptance in principle of this approach, and also provide detailed technical standards for its implementation. These include: (i) a taxable nexus based on a quantitative threshold of sales revenues; (ii) a methodology for defining the global consolidated profits of MNEs for tax purposes, and (iii) detailed technical standards for defining and quantifying the factors that reflect the real activities of MNEs in a jurisdiction (sales, assets and employees).
The time is now right to take up the roadmap outlined by the G-24. The work done shows that technical obstacles can be overcome, the challenge is essentially political. This paper aims to provide a blueprint for immediate measures that States can take, while engaging in deliberation at national, regional and international levels for a global drive towards practical and equitable reforms. Unitary taxation with formulary apportionment is the only fair and effective way to ensure taxation of MNEs where economic activities occur, as mandated by the G20. It can ensure that MNE profits are taxed once and only once, provide stability and certainty for business, and establish a basis for international tax rules fit for the 21st century.
* Also available in French, Spanish, Portuguese and Arabic.
TAXING MULTINATIONALS: THE BEPS PROPOSALS AND ALTERNATIVES
BEPS Monitoring Group, 6 July 2023
This briefing by the BEPS Monitoring Group (BMG) analyses the outcomes of the latest phase of the G20/OECD project on base erosion and profit shifting, and outlines options and alternatives, especially for developing countries. The BMG is a network of experts on various aspects of international tax, set up by a number of civil society organizations which research and campaign for tax justice including the Global Alliance for Tax Justice, Red de Justicia Fiscal de America Latina y el Caribe, Tax Justice Network, Christian Aid, Action Aid, Oxfam, and Tax Research UK. This report has not been approved in advance by these organizations, which do not necessarily accept every detail or specific point made here, but they support the work of the BMG and endorse its general perspectives. It is based on previous reports, and has been drafted by South Centre’s Abdul Muheet Chowdhary, Alex Cobham, Emmanuel Eze, Tommaso Faccio, Jeffery Kadet, Bob Michel, and Sol Picciotto.
Global Minimum Taxation of Multinationals: Opportunities and risks for some African States
By AMAGLO Kokou Essegbe, KOUEVI Tsotso and ADJEYI Kodzo Senyo
To face the challenges posed by the digitization of the economy, the OECD’s Inclusive Framework has developed two Pillars to address tax base erosion and profit shifting. The objective of Pillar Two is to define the minimum amount of tax to be paid by multinational enterprises in the jurisdictions where they operate. The OECD’s Inclusive Framework has adopted an average effective rate of 15% for this purpose. The objective of this study is to show whether the implementation of Pillar Two in African jurisdictions constitutes an opportunity or a risk for them.
The results show that it is an opportunity for countries with a low effective tax rate and a risk for countries with a high effective tax rate. Therefore, setting a 15% income tax rate for non-resident multinationals is an opportunity for some African countries. For it would constitute for these countries a source of additional tax revenue mobilization. For this reform to be an opportunity for Africa, however, the minimum effective tax rate must be raised to at least 20%, as was demanded by the African Tax Administration Forum (ATAF).
The risk that lies in the application of an effective rate of 15% for Africa as a whole is that some African countries might have to reduce their effective tax rate. This would be a loss of revenue for those African countries. Since most countries in the African jurisdiction have effective tax rates and statutory corporate income tax rates that are more than 20 percent, above the set average effective rate, multinationals would seek to shift their profits to the countries with the most advantageous taxation. This could lead to a transfer of profits to other jurisdictions.
Enforcing Secondary Taxing Rights: Subject to Tax Rule in the UN Model Tax Convention
By Abdul Muheet Chowdhary and Sebastien Babou Diasso
The Global Anti Base Erosion (GloBE) Rules under OECD’s Pillar Two recommendations, with a minimum effective tax rate of 15%, are expected to play a significant role to end the ‘race to the bottom’ in corporate taxation, which is one of the main drivers of profit shifting. However, the thrust of these rules is designed in a manner to give priority to the developed countries. In this light, the Subject to Tax Rule (STTR), which is a treaty-based rule that allows source jurisdictions to impose limited source taxation on certain payments that are taxed below a minimum rate in the country of residence, is of extreme significance for the developing countries. Under Pillar Two, application of STTR is restricted to base eroding payments or mobile income between related parties only, which does not address Base Erosion and Profit Shifting (BEPS) concerns in an entirety. That apart, the withholding tax rate of 9% proposed by the OECD may not result in generation of significant resources for the developing countries. In this light, developing countries keenly expect that the UN Tax Committee should devise an STTR that is simple to operate, has a broad scope covering all payments in a tax treaty and imposes a higher withholding tax closer to 15% to bring meaningful revenues for them. Also, developing countries desire that STTR provisions may be introduced at the earliest so as to speedily implement them through the UN Multilateral Instrument under contemplation. This Policy Brief also examines existing average withholding tax rates on interest and royalty payments in existing tax treaties of 48 South Centre and 52 G-77+China Member States and finds that out of a total of 100 developing countries, only 25 would stand to benefit from the STTR in its restricted form in Pillar Two, further strengthening the need for an improved version formulated by the United Nations.
Taxing Big Tech: Policy Options for Developing Countries
By Abdul Muheet Chowdhary and Sébastien Babou Diasso
Even as the COVID-19 crisis wreaked havoc on the global economy, it gave rise to a small set of winners, namely Big Tech. The increasing prevalence of remote work and an acceleration of the digitalization of the economy allowed Big Tech companies to raise enormous revenues during the pandemic, which in some cases dwarfed the gross domestic product (GDP) of several countries. This policy brief explores the rising untaxed profits of Big Tech in particular, and the digitalized economy in general, and explains why the existing rules are insufficient. It also critically examines the solution that has been devised by the Organisation for Economic Co-operation and Development (OECD), an intergovernmental organization of developed countries. Finally, it outlines alternative policy options that are more suitable for developing countries to tax the profits of Big Tech.
Revenue Effects of the Global Minimum Corporate Tax Rate for African Economies
By Seydou Coulibaly
This policy brief provides the first piece of empirical evidence on the revenue implications of the recent global minimum tax rate reform agreement for African economies. We implement a regression discontinuity design to evaluate the effect of having an effective corporate tax rate of at least 15% on tax revenue collection for a panel of 28 African economies over the period 2000-2020.
The estimation results indicate that the implementation of the global minimum effective corporate tax rate of 15% proposed under Pillar II of the Organisation for Economic Co-operation and Development (OECD) Two Pillar Solution has a positive but not statistically significant likely impact on corporate tax revenue and total tax revenue at the conventional significance levels. This suggests that the global minimum tax deal is unlikely to increase tax revenue for African economies. These findings exhort the Inclusive Framework and all the stakeholders of the global tax reform negotiations to consider revising the global minimum tax rate rules to ensure that the agreement will effectively benefit African countries through better tax revenue collection.
Evaluating the Impact of Pillars One and Two
By Suranjali Tandon and Chetan Rao
The proposed OECD Pillar One and Two reforms mark a significant shift in the way large multinational enterprises are taxed on their global incomes. However, while considering the reform at the proposed scale tax administrators must be able to compare the revenue gains with alternatives. This paper uses open-source data to provide tentative estimates of the impact of Pillars One and Two. The methodology has been detailed so that administrators can replicate it for comparison. Further, the paper provides an assessment from the perspective of developing countries of some of the key design elements of the proposals so as to understand whether they are administrable and to foresee possible challenges.
Impact of a Minimum Tax Rate under the Pillar Two Solution on Small Island Developing States
By Kuldeep Sharma
The Research Paper commences with an overview of Pillar One and Pillar Two followed by detailed discussions on salient provisions of Pillar Two.
Pillar Two is envisaged to have a widespread impact on Small Island Developing States (SIDS) which are a distinct group of 38 United Nations (UN) Member States and 20 Non-UN Members/Associate Members of UN regional commissions that are exposed to unique social, economic and environmental vulnerabilities. In all, 36 SIDS that are members of the Group of Seventy-Seven (G-77) have been analysed, namely, Antigua and Barbuda, Bahamas, Bahrain, Barbados, Belize, Cabo Verde, Comoros, Cuba, Dominica, Dominican Republic, Fiji, Grenada, Guinea-Bissau, Guyana, Haiti, Jamaica, Kiribati, Maldives, Marshall Islands, Mauritius, Federated States of Micronesia, Nauru, Papua New Guinea, Samoa, São Tomé and Príncipe, Seychelles, Singapore, Solomon Islands, St. Kitts and Nevis, St. Lucia, St. Vincent and the Grenadines, Suriname, Timor-Leste, Tonga, Trinidad and Tobago, and Vanuatu.
