AbstractBackgroundAlthough Medicaid coverage of treatment for children with autism spectrum disorder (ASD) is expanding, we know little about when children receive speech‐language, occupational and/or physical therapy. The objective of this study was to examine the relationships between predisposing, enabling and need characteristics and utilization of speech‐language, occupational and physical therapy by diagnosis of ASD.MethodsWe integrated administrative, Medicaid and Census data using a large sample of children with ASD who enrolled in a 1915(c) Home and Community Based Medicaid waiver in a south‐eastern state (N= 1,968) to explore (1) the percent of treatment utilization by ASD diagnosis, (2) the type of therapy utilized and (3) the predisposing, enabling and need characteristics associated with utilization.ResultsThe percent of utilization was 71%; 65.8% utilized SLT, 33.4% utilized OT and 18.4% utilized PT. Enabling (i.e., urbanicity, age of diagnosis and early intervention programme enrolment) and need (i.e., intellectual disability) characteristics were associated with utilization whereas predisposing social characteristics (i.e., sex and child race‐ethnicity and neighbourhood racial composition, poverty and affluence) were not associated with utilization.ConclusionsFindings highlight the value in monitoring when children begin treatment. As governments in the United States and globally work to maximize children's potential, additional research that can inform efforts to facilitate earlier utilization will be key to promoting optimal outcomes.