Eighty children with early autism spectrum disorder (ASD) diagnoses (under 36 months) were identified using a chart abstraction protocol applied to early intervention charts. Parents filled out questionnaires by mail when the children were school-aged (ages 6–16 years). Similar to previous studies, approximately 20 % no longer had ASD diagnoses; the other participants were assigned to Moderate/Severe versus Mild ASD outcome groups. These three groups were compared across several variables, including diagnostic features and functional features including adaptive behavior, social experiences, medication use, and school placement. The findings expand our knowledge about outcomes in longitudinal studies of children with ASD, as well as provide support for using relatively indirect methods (chart review, parent questionnaire) to gather this type of information.