Abstract Object Cranioplasty has been considered for several decades as a protective and cosmetic procedure. It has recently been postulated that cranioplasty may have a therapeutic role, and improve the patient’s functional outcome after decompressive craniectomy (DC). The appropriate timing for cranioplasty remains unknown. In our current study, we review the literature for evaluating the relationship of cranioplasty timing and its complication rate and outcome. Methods The PubMed database was searched to identify any relevant articles. The following terms were used as keywords: “cranioplasty”, “timing cranioplasty”, “early cranioplasty”, “late cranioplasty”, “delayed cranioplasty”, “early versus late cranioplasty”. Clinical studies with more than 10 participants, and closed head injury as the underlying cause for DC were included in our study. The study design, the timing performing cranioplasty, the complication rate, and the patients’ outcome were evaluated. Results Ten clinical series met our inclusion criteria. The observed complication rate associated to cranioplasty after DC is not negligible. Several reports have demonstrated that late cranioplasty may minimize procedure-associated complications. Early cranioplasty has been associated with complications, but improves CSF dynamics, and regional cerebral perfusion and metabolism, minimizes the complications from a sunken scalp, reduces the overall length of hospitalization, and thus the overall cost of care. Conclusions Cranioplasty is a relatively simple procedure that is nevertheless burdened by considerable morbidity. However, an early cranioplasty procedure may improve the outcome in selected cases. Prospective, large-scale studies are necessary to outline the actual complication rate, the neurological outcome, and define the optimal timing for a cranioplasty.