Since their inception in 1997, Arizona policymakers have debated the merits of Arizona’s income tax credits for contributions to certified school tuition organizations (STOs), though the programs have grown year over year. This study aims to answer lingering questions about the beneficiaries of STO scholarships. First, using publicly available reports from the Arizona Department of Revenue, the Arizona Board of Education, and American Community Survey 5-year estimates, multiple regression analysis indicates a weakly negative relationship between scholarship dollars and family income but no statistically significant effect of public-school quality on scholarship dollars. Second, using data from a survey of parents whose students’ attend Arizona private schools, logistic regression suggests a weakly negative relationship between scholarship utilization and family income, with public school quality having no statistically significant effect on STO scholarship utilization. Moreover, multiple regression analysis again shows a weakly negative relationship between scholarship dollars and family income but no statistically significant relationship between public school quality and scholarship dollars. This paper concludes by offering policy suggestions to improve the accountability of these programs.