This study provided a description of types and dimensions of informal and formal social support among aging parental caregivers of adult children diagnosed with autism spectrum disorder (ASD). Parents participated in a web-based survey regarding use of and satisfaction with social support services for parents or their adult children. Results indicated that many parents participated in autism support groups (27.5%), with psychiatric services (48.8%), counseling (40.6%), and financial assistance (39.7%) the most commonly used formal social supports.