Oklahoma offers state-funded prekindergarten (preK) to all four-year-olds. The Regional Educational Laboratory Southwest Early Childhood Education research partnership in Oklahoma requested more comprehensive evidence on disparities in student participation in state-funded preK that might indicate challenges in program access or use. The study used Oklahoma State Department of Education administrative records to calculate the percentages of first-time public school kindergarten students in the 2014/15–2018/19 school years who participated in state-funded preK in the prior year, overall and for subgroups defined by geographic locale and student characteristics. Statistical models were used to estimate the relationships between student and district characteristics and local availability of preK options (measured as estimated travel time) and students’ participation in state-funded preK. (author abstract)