There is limited literature examining the adaptive functioning of adolescents with autism spectrum disorder (ASD). This study aimed to (a) document Vineland Adaptive Behavior Scales (VABS-3) and Adaptive Behavior Assessment System (ABAS-3) adaptive behavior profiles of adolescents with ASD; (b) examine the comparability of the two measures; and (c) assess potential discrepancies between IQ and adaptive behaviors. Participants included 14- to 18-year-olds with ASD without intellectual disability. Significant adaptive skills deficits were observed with most scores at least one standard deviation below the mean. Relative weaknesses were observed for social and daily living skills. The absolute magnitude of VABS-3 and ABAS-3 scores differed. There were significant discrepancies between IQ and adaptive functioning. These findings have implications for clinicians and researchers.