A DOCTRINAL AND INSTITUTIONAL REVIEW OF PERSONAL INCOME TAX LAWS IN NIGERIA (1960–2025)

This study investigates the enduring structural and institutional constraints affecting Nigeria’s personal income tax system from 1960 to 2025, focusing on issues of equity, taxpayer compliance, and administrative efficiency. The objective is to assess the extent to which successive legislative reforms have addressed these challenges and enhanced revenue mobilisation. Adopting a qualitative doctrinal and historical research approach, the study traces the development of personal income tax legislation from the Income Tax Management Act 1961 through the Personal Income Tax Act 1993 to the Nigeria Tax Act 2025. The analysis is anchored on the Ability-to-Pay, Equity, Optimal Tax, Tax Compliance, and Institutional theoretical frameworks. The findings reveal that although successive reforms have improved legal clarity, progressivity, and the formal inclusiveness of the tax system, persistent weaknesses in institutional capacity, inconsistent enforcement, and low levels of taxpayer trust continue to undermine compliance and limit revenue performance. While the Nigeria Tax Act 2025 introduces significant innovations—particularly in expanding exemptions for low-income earners, accommodating digital and cross-border income, and promoting administrative modernisation—legislative reform alone has proven insufficient to deliver optimal outcomes without corresponding institutional strengthening. The study concludes by recommending sustained investment in tax administration, enforcement mechanisms, and trust-building measures to complement legal reforms. It contributes to the literature by offering a longitudinal doctrinal analysis of Nigeria’s personal income tax regime and by providing policy-relevant insights for enhancing equity, compliance, and revenue sustainability in emerging economies.