Performance patterns on verbal subtests from the WISC-IV were compared between a clinically-referred sample of children with either autism spectrum disorders (ASD) or attention deficit/hyperactivity disorder (ADHD). Children with ASD demonstrated a statistically significant stepwise pattern where performance on Similarities was best, followed by Vocabulary, then Comprehension. Although children with ASD and ADHD share multiple behavioral features, this pattern was not observed for those with ADHD. Greater deficits in social reasoning and verbal formulation for children with ASD (compared to ADHD) are hypothesized to account for this observed difference in their performance pattern. Clinical implications, including use of this identified pattern in combination with other symptoms suggestive of ASD in referral decision making are discussed.