Orthotopic liver transplantation (OLT) is the only effective treatment for end-stage liver disease. Although most patients do well and are discharged promptly, some require prolonged length of stay (PLOS). The prevalence of PLOS, associated factors, and their impact on survival are not well defined. We reviewed our adult OLT database for patients who survived ΟΎ 30 days. PLOS was defined as hospitalization ΟΎ 30 days following OLT. Of 521 OLT recipients, 68 (13%) had PLOS with a median duration of 50 days versus only 10 days for patients discharged within 30 days. Significant differences in pre-OLT variables between patients with and without PLOS included the mean wait list time (P Ο 0.001), hospitalization at the time of OLT (P Ο 0.001), and prior OLT (P Ο 0.041). Factors independently associated with PLOS included intensive care unit status at the time of OLT [odds ratio (OR), 4; 95% confidence interval (CI), 1.6-10.4], OLT prior to Model for End-Stage Liver Disease implementation (OR, 2.27; 95% CI, 1.04-5.26), in-hospital post-OLT bacterial infection (OR, 9.34; 95% CI, 4.65-18.86), gastrointestinal bleeding (OR, 4.34; 95% CI, 1.4-14.08), renal failure (OR, 10.86; 95% CI, 5.07-23.25), and allograft rejection (OR, 3.7; 95% CI, 1.23-11.11). One-year graft survival and patient survival were significantly less in those with PLOS (for both, P Ο½ 0.0001). Among PLOS patients, factors independently associated with increased 1-year mortality were donor age (OR, 1.07; 95% CI, 1.009-1.13), primary diagnosis of hepatitis C virus (OR, 6.89; 95% CI, 1.40-34.48), in-hospital post-OLT bacterial infection (OR, 13.3; 95% CI, 2.11-83.33), and cardiac complications (OR, 20.4; 95% CI, 1.51-250; c-statistic for the model, 0.85). In conclusion, PLOS following OLT is associated with a significant decrease in survival despite a marked increase in cost and resource utilization. Efforts to modify those factors that contribute to PLOS may reduce this event, improve survival, and reduce OLT-associated costs.