The goals of this study are to identify the prevalence of children with autism spectrum disorder (ASD) entering out-of-home care and to focus attention on length of stay and placement stability. To achieve these goals, this study links Illinois administrative data with Medicaid records. Overall, 2.4% of the sample has a diagnosis of ASD. The median length of stay for children with ASD is 1.6 times longer than children without ASD. A latent class analysis identifies three distinct profiles of movement: escalating, de-escalating, and continuous. Study findings are discussed in the context of service needs of children with ASD.