Corruption can undermine taxpayers’ trust in the fairness of how public funds are allocated and tax procedures are carried out. While the relationship between corruption and tax system unfairness is largely unexplored, a significant body of knowledge covers these constructs in isolation. This study assesses the influence of corruption on Ugandan small and medium enterprises (SMEs’) perception of tax fairness. The authors use a thematic analysis on semi-structured interview data to assess the effects of corruption on tax fairness perceptions. The findings reveal four types of corruption: petty corruption, petty tax corruption, political corruption, and grand corruption. These have significant influence on income tax unfairness perceptions among SME firms. Tax and government officers as well as the political elite who demand bribes, embezzle taxpayers’ funds, and discriminate among taxpayers based on tribal sentiments incite taxpayers’ distributive and procedural tax unfairness perceptions. The results demonstrate that the government must strive to create an honest bureaucracy and tax administration to improve tax fairness perceptions. This can be done by allowing anti-corruption agencies to work professionally and independently of political influence.