Effect of Corporate Governance on Auditor Choice among Listed Non-Financial Firms in Nigeria

This study investigates the effect of corporate governance on auditor choice among listed nonfinancial firms in Nigeria. The research examines how corporate governance mechanisms specifically board size, board independence, board gender diversity, and audit committee expertise alongside ownership structure variables (ownership concentration and institutional ownership) and firm size, influence the probability of selecting Big Four audit firms. Using an ex post facto research design, secondary data were collected from the annual reports of 103 listed non-financial firms on the Nigerian Exchange Group (NGX) over a seven-year period (2018–2024), yielding 623 firm-year observations. A census approach was employed, and the data were analyzed using a Random-Effects Logistic regression model following diagnostic tests that confirmed the absence of heteroskedasticity and multicollinearity. The findings reveal that board size, audit committee expertise, and firm size have significant positive effects on the likelihood of engaging Big Four auditors, while board independence, board gender diversity, ownership concentration, and institutional ownership show no statistically significant influence on auditor choice. The study concludes that specific corporate governance attributes, particularly audit committee expertise and board size, along with firm characteristics such as firm size, are meaningful determinants of auditor selection in Nigeria's non-financial sector. It recommends that firms seeking enhanced audit quality prioritize the appointment of financially qualified audit committee members and maintain appropriately sized boards, while regulators should strengthen requirements for audit committee competence