Clinical genetic testing is recommended for individuals diagnosed with autism spectrum disorder. There are only a few reports of how these recommendations are followed and especially missing for European countries. We aimed to analyze the rate of access, utilization, and awareness of clinical genetic testing among autistic individuals in Sweden through online surveys targeting parents with at least one autistic child and autistic adolescents (from 15 years) and adults. In total, 868 parents of autistic children and 213 autistic adolescents or adults completed the survey. Only 9.1% (n = 79) of parents and 2.8% (n = 6) of autistic adolescents/adults reported having received a referral for clinical genetic testing after autism spectrum disorder diagnosis. The autistic children offered a referral were younger at diagnosis (p < 0.001) and more likely to have an additional neurodevelopmental diagnosis (p < 0.01), including intellectual disability (p < 0.001) or a language disorder (p < 0.001). Genetic counseling was provided to less than half of the families that were referred for clinical genetic testing. Finally, we report that both respondent groups preferred to be informed by written text and an expert in genetics about clinical genetic testing. This study highlights a lack of awareness and access to clinical genetic testing after autism spectrum disorder diagnosis in Sweden and demonstrates the need for additional studies on how clinical guidelines for genetic testing are followed in different countries.