The recommended treatment for craniosynostosis, is cranial vault expansion to prevent increased intracranial pressure and optimize developmental outcomes. Some patients complain about postoperative headaches and occasionally require revision to treat increased intracranial pressure. This study examines whether specific factors are associated with an increased risk of postoperative headaches or intracranial hypertension. This retrospective cohort included patients with craniosynostosis from 1995 and 2010. Primary outcomes included headaches and delayed intracranial hypertension. Logistic regression was used to evaluate the associations with clinical characteristics. The cohort included 383 patients, of whom 127 (33 percent) complained of headaches. The positive predictive value of a headache indicating intracranial hypertension was only 9.4 percent among all patients and 6.7 percent among patients with nonsyndromic craniosynostosis. Headaches occurring in the morning, more than once per week, and associated with nausea, vomiting, or decreased activity level were most likely to be associated with delayed intracranial hypertension. Only 21 patients (6 percent) required revision surgery, and these patients were more likely to have syndromic craniosynostosis (OR, 5.6; 95 percent CI, 2.1 to 14.9), Chiari malformation (OR, 5.8; 95 percent CI, 1.7 to 19.5), or secondary craniosynostosis (additional sutures fused on the 2-year postoperative CT scan) (OR, 5.4; 95 percent CI, 2.2 to 13.5). Headaches are common after cranial vault remodeling but are not very predictive of who will need revision surgery for intracranial hypertension. Patients with specific headache characteristics, syndromic craniosynostosis, secondary synostosis, and Chiari malformations have the highest risk of developing delayed intracranial hypertension. Risk, III.