Background <p>Early intervention (EI) is considered important for social and adaptive outcomes in autism spectrum disorder (ASD), yet evidence from Jordan is limited. In this study, social decision-making competencies include self-control, social awareness, group participation, and decision-making/social problem-solving. Adaptive outcomes refer to mothers’ descriptions of everyday functional changes in real-life settings.</p> Methods <p>Mothers of children and adolescents with ASD in Jordan (<i>n</i> = 119) completed structured questionnaires rating these competencies and related behaviors. EI history was based on mothers’ reports of prior structured EI services. Quantitative comparisons were conducted between an EI-history group and a no-EI group, stratified by age (6–12; 13–16) and pooled (6–16). A subsample completed in-depth interviews to contextualize questionnaire patterns; qualitative data were analyzed using reflexive thematic analysis within an explanatory sequential mixed-methods design.</p> Results <p>In pooled analyses (6–16), the EI-history group showed higher scores across all three dimensions: Self-Control (adjusted p = 0.015), Social Awareness/Group Participation (adjusted p &lt; 0.001), and Decision-Making/Social Problem-Solving (adjusted p = 0.002). In children aged 6–12, all three dimensions were higher in the EI-history group: Self-Control (adjusted p = 0.012), Social Awareness/Group Participation (adjusted p &lt; 0.001), and Decision-Making/Social Problem-Solving (adjusted p &lt; 0.001). Among adolescents aged 13–16, no domain differences were detected. Interviews were broadly consistent with these patterns, describing perceived everyday gains mainly in younger children.</p> Conclusion <p>Mother-reported ratings varied by EI history for selected competencies and by age. Findings support the importance of improving access to EI in Jordan, and structured follow-up supports may be needed into adolescence.</p>