Objectives/Hypotheses The endoscopic endonasal approach (EEA) is the workhorse endoscopic procedure for sellar and parasellar pathology. Various reconstruction techniques have been reported following EEA surgery, ranging from no reconstruction to vascularized flaps. We review our institution's experience with sellar reconstruction following EEA and propose an evidence-based algorithm. Design Retrospective review. Setting Tertiary academic medical center. Participants Patients who underwent endoscopic EEA surgery for sellar or parasellar pathology between March 1, 2013 and August 31, 2016. Main Outcome Measures Patient demographic and clinicopathologic data were collected. Outcome measures included intraoperative and postoperative cerebrospinal fluid (CSF) leak rates and extent of resection (gross or subtotal). Results Three hundred consecutive patients were included. Depending on the presence and grade of intraoperative CSF leak, cases were reconstructed using either a free mucosal graft (FMG) or nasoseptal flap (NSF). Intraoperative and postoperative CSF leak rates were 30.7% and 2.3%, respectively. Multivariable logistic regression found that intraoperative CSF leak was associated with recurrent disease (odds ratio [OR] 2.47, p = 0.004), with no apparent predictors of postoperative CSF leak. Conclusions Based on this large series, we propose the following algorithm for sellar reconstruction: FMG for no CSF leak; fat graft + FMG ± rigid fixation for low-grade leaks; and fat graft + NSF ± rigid fixation for high-grade leaks.