Objectives Latino young adults with autism spectrum disorder (ASD) face many challenges during the transition to adulthood, particularly regarding executive functioning (EF) and mental health symptom management. Latinos with ASD are particularly underserved, with existing supports often neglecting these critical areas. The study aims to evaluate a culturally and linguistically tailored intervention to better support Latino young adults by improving their adaptive functioning to enhance social outcomes and quality of life. Methods The culturally adapted and translated intervention, called ¡Iniciando! la Adultez, is a 12-week therapy program based on an evidence-based treatment (Launching! to Adulthood). The present study involved young adults with ASD (n = 26) and their Spanish-speaking parents (n = 38). Participants completed measures at baseline, mid-treatment, and post-treatment. Results The ¡Iniciando! la Adultez program led to significant improvements in social domains (e.g. cognition, motivation), and improvements in adaptive functioning, EF, quality of life, self-efficacy, and emotion regulation. Parental stress and caregiver burden, however, did not show significant changes. Conclusions Tailored, holistic interventions like ¡Iniciando! la Adultez are useful for supporting autistic young adults. These programs effectively address critical gaps in EF and mental health management, especially for Latino individuals, promoting better outcomes during the transition to adulthood.