Tax Compliance and Revenue Administration in Osun State Internal Revenue Service

This study investigates the determinants of tax compliance and their implications for revenue administration in the Osun State Internal Revenue Service (OSIRS), located in Nigeria's South West geopolitical zone. Tax non-compliance remains a chronic challenge for state governments seeking to increase internally generated revenues and reduce dependence on federal transfers. The study employs a survey design, collecting data from 265 registered individual and corporate taxpayers, tax administrators, and civil society representatives in Osogbo, the state capital. Regression analysis is used to identify the most significant predictors of taxpayer compliance behaviour. The Slippery Slope Framework of Tax Compliance provides the theoretical foundation, arguing that compliance is shaped by the combined effects of the power of tax authorities to detect and punish non-compliance and the trust taxpayers place in those authorities. Findings reveal that trust in government, perceived fairness of the tax system, and awareness of tax obligations are the strongest predictors of compliance, while the fear of penalties is a relatively weak motivator. Tax education deficits, particularly among traders and small business operators, are identified as major compliance barriers. The study recommends the introduction of taxpayer education campaigns, simplification of tax filing procedures for informal sector operators, and the publication of government expenditure outcomes to build taxpayer trust. Keywords: tax compliance, revenue administration, Osun State, taxpayer behaviour, internally generated revenue.