This study aims to analyze the effect of tax knowledge, tax complexity, and tax justice on taxpayers' trust and tax compliance as well as the differences in tax compliance levels in South Sumatra. The research is explanatory and takes a quantitative approach. The method of data collection used a questionnaire containing the variables and documentation outlined by the study. The research questions were tested using hypothetical compliance scenarios, with 900 registered individual taxpayers from five major cities in South Sumatra as participants. The researchers used confirmatory factor analysis (CFA) with the structural equation modeling (SEM) approach. Results of the research show that (1) tax knowledge has no effect on taxpayers' trust, (2) tax complexity has no effect on taxpayers' trust, (3) tax justice has an effect on taxpayers' trust, (4) tax knowledge has no effect on tax compliance, (5) tax complexity has no effect on tax compliance, (6) tax justice has an effect on tax compliance, (7) taxpayers' trust has an effect on tax compliance, and (8) there were differences in the level of tax compliance after the implementation of the SMS blast program.