Purpose <p>This study aimed to assess executive functioning in everyday activities of participants with non-syndromic craniosynostosis, to compare their performance with a control group, to assess the relationship between the timing of surgery and executive functioning, and to determine the proportion of participants scoring in the clinical range for executive functions.</p> Methods <p>Twenty-nine participants with craniosynostosis and 30 controls were assessed with the parent version of the Behavior Rating Inventory of Executive Function 2 (BRIEF-2).</p> Results <p>Both groups scored similarly. However, the older the participant with craniosynostosis at the time of the surgery, the greater their difficulties in Task Initiation, Working Memory, Planning, and Monitoring. Only a small percentage (0–17%) of participants with craniosynostosis scored in the clinically significant range; this proportion was similar to that of the control group.</p> Conclusion <p>This study did not find substantial difficulties in executive functions in daily activities in participants with non-syndromic craniosynostosis, but it did find an association between late surgery and lower scores in some cold executive functions. The study suggests that early surgical intervention could have a potential neurodevelopmental benefit for children and adolescents with craniosynostosis.</p>