Health coverage of early intensive behavioral intervention (EIBI) for children with autism spectrum disorder is expanding. Yet there is no longitudinal research on patterns of or inequities in utilization of EIBI. We integrated state administrative records with Medicaid and Census data for children enrolled in an EIBI Medicaid waiver (N = 730) to identify and describe the type and prevalence of treatment utilization trajectories, and to examine the association between trajectory types and (a) child race-ethnicity and (b) neighborhood racial composition, poverty, affluence, and urbanicity. We identified four utilization trajectories (Low, Low-Moderate, Moderate, and High users). Race-ethnicity and neighborhood affluence were associated with trajectory membership. As coverage expands, policy makers should consider strategies to improve overall treatment utilization and enhance equity.