The disparity in absenteeism between kindergarteners with and without disabilities is a persistent phenomenon across schools in the United States and reflects ongoing systemic inequities that disadvantage young children with disabilities. Yet, evidence of factors underlying this disparity remains less well understood, limiting the ability for schools to transform how they support students with disabilities in ways that could help narrow the disparity. In our study, we investigate how a set of factors, grounded in a socioecological framework of absenteeism, correlates with chronic absenteeism in kindergarteners with and without disabilities. Importantly, we examine the extent to which distributional differences in these factors between children with and without disabilities explain the attendance disparity. Our study draws upon a nationally representative sample of N = 13,860 kindergarteners (52 % male, 48 % female, Mage = 5.5 years, n = 1240 with disabilities) from the Early Childhood Longitudinal Survey Kindergarten Class of 2010–11. We analyze our data using multiple logistic regression to identify significant factors that correlate with chronic absenteeism and leverage the Kitagawa-Blinder-Oaxaca decomposition method to describe how distributional differences in those factors contribute to absenteeism disparities. Results show that internalizing behaviors in students with disabilities and their parents’ health are significantly associated with chronic absenteeism as well as help explain the disparity (12 % and 3 % of the disparity, respectively). Importantly, since differences in internalizing behaviors can be generated, in part, by school practices and policies that treat early elementary students with disabilities inequitably, our work suggests that reducing gaps in early absenteeism may require schools to reduce exposure to experiences that can lead to internalizing problem behaviors in young children with disabilities. (author abstract)