加强简化以促进税收确定性和增长：经合组织提交给G20的报告

OECDReport totheG20 Enhancing Simplicity to Foster Tax Certainty OECD Report to the G20 2 This work was approved and declassified bythe Inclusive Framework on BEPSon15 September 2025. Thisdocument, as well as any data and map included herein, are without prejudice to the status of or sovereignty overany territory, to the delimitation of international frontiers and boundaries and to the name of any territory, city or area. Pleasecite this publication as: OECD (2025),Enhancing Simplicity to Foster Tax Certainty and Growth:OECD Report to the G20, OECD Publishing, Paris,https://doi.org/10.1787/086f71ab-en. Corrigenda to OECD publications may be found at:https://www.oecd.org/en/publications/support/corrigenda.html.© OECD2025 Attribution4.0 International (CCBY4.0) Table of contents Executive summary4 1 Introduction6 Inherent complexities in the taxation of cross-border businessactivityThis report 67 2 Hallmarks of simplicity in tax rules8 Evaluating hallmarks of simplicityDrivers of complexity in cross-border taxation rules 811 3 The role of multilateral co-operation in reducing complexity Additional drivers of complexity in the context of international co-operation15Benefits of multilateral co-operation in counteracting complexity in cross-border taxation17Tools for reducing complexity andpromoting certainty: progress to date18 4 Opportunities to enhance tax simplicity and certainty: areas for further focus21 A simplicity checklist22Process for designing solutions and outputs23 5 Conclusions and next steps References 36 Executive summary Taxation of cross-border business activity is inherently complex fortaxpayers and governments. Taxpayersoperating across borders must understand, comply with and bear the consequences of the interactions of This inherent complexity can be mitigated by effective internationalco-operation designed toavoid double Significant reforms to the cross-border business taxation landscape have taken place, particularly over thelast decade, many of which were championed by the G20. To promote certainty and stability and improvethe integrity of the cross-border business tax system, jurisdictions across the world have made legislative Inthe current environment,complexity in the cross-border business taxation landscape remainschallenging. In part thisreflects the increased integration of the global economy and related supply chainsand the sophistication of business models (including the significance of intangible property). It is also afunction of the speed of changes to the cross-border business taxation rules that have taken place in recent Lower capacity jurisdictions in particular have expressed their concern about complexity, including theadministrability of rules, and the collateral impact on the ability to protect their tax base. In some instances,concerns about complexity may hinder the adoption of new rules in the first place–because of perceived Taxpayers also have concerns about complexity and the related costs of compliance. This includes theconcern that compliance costs can be excessive relative to the tax at stake; the costs drain resources that There is therefore a need for international organisations such as the OECD and Inclusive Framework, anddomestic governments to consider simplification. Benefits of simplification can include: •Improving ease for taxpayers in implementing the rules and reducing cost of compliance;•Improving the ease of administration, which can reduce costs for tax administrations or, over time,allow for deployment of tax administration resourceselsewhere; •Promoting voluntary compliance and improving investor confidence and growth;•Enabling greater consistency in interpretation of the rules which can prevent and limit tax disputes, In pursuing simplification, there is also a recognition of the need to balance other policy objectives whichmay pull in a different direction. For instance, an overly simple rule may not be sufficiently clear or fair inits application to vastly different fact patterns. Equally, an overly simple rule might be more susceptible to This report, prepared at the request of the South African G20 presidency, considers ways to bringsimplification, foster tax certainty and reduce compliance costs in the cross-border business tax system Chapter1of the reportacknowledgesthe inherent complexities in the taxation of cross-border businessactivities and describes the contribution this report is intended to make.Chapter2discusses the hallmarksof simplicity and drivers of complexity in the context of thedomestic rules which form the foundation forimplementing multilaterally agreed solutions and outputs. Chapter3explores the additional drivers of The conclusion and next steps in Chapter5identifyareas where further work could be explored, inconsultation with interested jurisdictions, organisations and business. Given the relevance of this topic tomany stakeholders, this report invites furtherdevelopment ofthe