A Local Government Revenue Collection System for Oyo State Internal Revenue Service

Revenue leakage in Nigerian local government areas represents a critical obstacle to fiscal sustainability and service delivery. This study develops a local government revenue collection system for the Oyo State Internal Revenue Service (OYIRS), targeting informal market traders and property owners in the South West geopolitical zone. The system is implemented using PHP, JavaScript, and a MySQL relational database, with a mobile USSD interface for taxpayers without smartphones. The development follows the waterfall model, providing sequential milestones appropriate for a government-grade deployment. Core modules include taxpayer registration, levy assessment, payment tracking, receipt generation, and arrears management. A three-month pilot was conducted in Ibadan North and Lagelu local government areas involving 200 traders and 18 revenue officers. Pilot results show a 45 percent increase in levy collection compliance and a 38 percent reduction in revenue officer processing time per taxpayer. The study flags data privacy and taxpayer trust as implementation challenges, recommending transparent public communication from OYIRS prior to rollout. This research provides a replicable digital revenue framework scalable to other South West states struggling with informal sector taxation. It also reinforces the role of purpose-built software engineering in strengthening public financial management in Nigerian subnational governments. Keywords: revenue collection, local government, USSD, Oyo State, tax compliance