THE PARADIGM OF CORPORATE TAX BASE FORMATION: COMPARATIVE ANALYSIS OF CORPORATE INCOME TAX SYSTEMS IN UKRAINE AND INTERNATIONAL PRACTICE

Abstract

Relevance of the study. In the context of the transformation of the international tax environment and increasing global tax competition, the issue of corporate tax base formation is becoming increasingly important. Corporate income tax serves not only as a key source of public revenues but also as a regulatory instrument influencing investment activity, corporate financing structure, and economic behavior of firms. At the same time, differences in approaches to determining the taxable base across countries necessitate their conceptual understanding and comparative analysis. Purpose. The purpose of the article is to examine the paradigm of corporate tax base formation and to conduct a comparative analysis of the institutional and methodological foundations of determining the taxable profit in the tax systems of Ukraine and the United States. Research methods / Methodology. The methodological framework of the study is based on a combination of general scientific and specialized methods, including abstraction, systems analysis, institutional analysis, and comparative analysis. The research relies on the analysis of tax legislation in Ukraine and the United States, as well as contemporary theoretical approaches to corporate taxation. Findings. The study identifies two dominant paradigms of corporate tax base formation: a model based on accounting profit and a model based on the autonomous determination of taxable income. It is established that the Ukrainian corporate tax system relies on the integration of accounting and tax rules through tax adjustments, whereas the United States model is characterized by a high degree of tax law autonomy and the application of detailed rules, deductions, and limitations. The findings demonstrate that these differences are systemic and reflect distinct institutional approaches to the organization of tax systems. It is also shown that the U.S. model provides more advanced mechanisms for protecting the tax base, particularly in the areas of financial expense regulation and international taxation, while the Ukrainian model ensures greater consistency between financial reporting and tax calculations. тOriginality / Value. The originality of the study lies in the systemic interpretation of the corporate tax base as a component of the institutional architecture of the tax system and in identifying conceptual differences between its formation models. The practical value of the research is related to the potential application of its findings for improving corporate taxation mechanisms in Ukraine with regard to international experience.