This study examines the multilevel effect and determinant factors on charter school enrollment size. From the managerial perspective, charter school size is important because student enrollment may influence academic performance as well as financial capacity related to charter school operation and contract renewal. For empirical analysis, Hierarchical Linear Models consider multi-level effects and causality in charter schools and school districts according to charter school enrollment size. Through HLM analysis, we found some important implications to consider. First, there is a multilevel effect from school and school district level. Second, five significant variables are related to school performance, school finance, and school district characteristics. Third, Florida showed very unique patterns and characteristics of charter school enrollment size with regard to white student population and median household income.