Taxation plays a vital role in revenue generation for governments, especially at the state level, where taxes fund critical public services and infrastructure. However, tax avoidance and tax evasion pose significant challenges to effective revenue collection, leading to substantial financial losses. This study evaluates the impact of tax avoidance and tax evasion on revenue generation in Bauchi State, Nigeria. The research aims to examine the prevalence of these practices, identify their contributing factors, and assess their consequences on the state's economic development. Using both primary data, collected through surveys and interviews with tax officials and taxpayers, and secondary data from government tax records, the study explores the extent of noncompliance with tax obligations. The findings indicate that both tax avoidance and evasion are widespread, with weak enforcement, limited taxpayer education, and inadequate legal frameworks being primary contributors. As a result, Bauchi State experiences considerable revenue shortfalls, hindering its ability to invest in key sectors such as education, healthcare, and infrastructure. The study recommends strengthening tax enforcement mechanisms, increasing public awareness on the importance of tax compliance, and revising tax policies to ensure a more transparent and efficient system. The research highlights the critical need for reform to enhance revenue generation, foster economic growth, and improve the standard of living in Bauchi State.