Online course delivery continues to grow as a viable means of providing increased educational access to more students, but low student retention rates remain a major challenge. In this study, key institutional characteristics that influence student retention in postsecondary education are analyzed. These are student-faculty ratio, graduation rate, acceptance rate, enrollment rate, institutional aid rate, default rate, and institution type. Using multivariable regression analysis, our findings show that graduation rate, default rate, and college type were significantly associated with retention rate among online degree-granting institutions. Furthermore, graduation rate was found to be strongly positively linearly related with retention rate, while default rate was strongly negatively linearly related with retention rate. Overall these findings have direct implications on the planning and management of online instruction.