Board Gender Diversity and Tax Avoidance in Nigeria

This study investigates the relationship between board gender diversity and corporate tax avoidance among firms listed on the Nigerian Exchange Group (NGX) over the period 2010–2025. Drawing on a panel dataset of 148 NGX-listed firms and employing fixed-effects and random-effects panel regression techniques, the study examines whether the presence of female directors on corporate boards mitigates or facilitates tax avoidance behaviour. Tax avoidance is operationalised through the effective tax rate (ETR) and book-tax difference (BTD), while board gender diversity is measured by the proportion of female directors on the board and the Blau index. The study controls for firm size, return on assets (ROA), leverage, auditor quality (Big 4 dummy), industry effects, and year effects. Anchored on agency theory, resource dependence theory, and the upper echelons theory, results reveal that greater board gender diversity is significantly and negatively associated with tax avoidance, suggesting that female directors serve as effective monitors and ethical gatekeepers within Nigerian corporate boardrooms. These findings are robust across alternative specifications and post-estimation diagnostics. The study contributes to the growing body of literature on corporate governance and tax behaviour in African emerging markets, offering novel insights for policymakers, regulators, and corporate governance practitioners in Nigeria and comparable economies. The findings carry significant implications for the Federal Inland Revenue Service (FIRS), the Securities and Exchange Commission (SEC Nigeria), and NGX regulators in the design of governance-compliant tax frameworks.