Autism spectrum conditions (ASC) has recently been associated with increased risk of suicidality. However, no studies have explored how autistic traits may interact with current models of suicidal behavior in a non‐clinical population. The current study therefore explored how self‐reported autistic traits interact with perceived burdensomeness and thwarted belongingness in predicting suicidal behavior, in the context of the Interpersonal‐Psychological Theory of Suicide (IPTS). 163 young adults (aged 18–30 years) completed an online survey including measures of thwarted belonging and perceived burdensomeness (Interpersonal Needs Questionnaire), self‐reported autistic traits (Autism Spectrum Quotient), current depression (Centre for Epidemiological Studies Depression Scale), and lifetime suicidality (Suicide Behavior Questionnaire‐Revised). Results showed that burdensomeness and thwarted belonging significantly mediated the relationship between autistic traits and suicidal behavior. Both depression and autistic traits significantly predicted thwarted belonging and perceived burdensomeness. Autistic traits did not significantly moderate the relationship between suicidal behavior and thwarted belonging or perceived burdensomeness. Results suggest that the IPTS provides a useful framework for understanding the influence of autistic traits on suicidal behavior. However, the psychometric properties of these measures need be explored in those with clinically confirmed diagnosis of ASC. Autism Res. 2017. © 2017 The Authors Autism Research published by International Society for Autism Research and Wiley Periodicals, Inc.