Dysnatremias are a rare but significant event in liver transplantation. While recipient pre-transplant hypernatremia has been demonstrated to increase post-transplant mortality, the degree of hypernatremia and the impact of its resolution have been less well characterized. Here, we used multivariate Cox regression with a comprehensive list of donor and recipient factors in order to conduct a robust multivariate retrospective database study of 54,311 United Network for Organ Sharing (UNOS) liver transplant patients to analyze the effect of pre-transplant serum sodium on post-transplant mortality, post-transplant length of hospitalization, and post-transplant graft survival. Mortality and graft failure increased in a stepwise fashion with increasing pre-transplant hypernatremia: 145 -150mEq/L (HR=1.118 and HR=1.113), 150-155mEq/L (HR=1.324 and HR=1.306), and > 155mEq/L (HR=1.623 and HR=1.661). Pre-transplant hypo- and hypernatremia also increased length of post-transplant hospitalization: < 125mEq/L (HR=1.098), 125-130mEq/L (HR=1.060), 145 -150mEq/L (HR=1.140), and 150-155mEq/L (HR=1.358). Resolution of hypernatremia showed no significant difference in mortality compared with normonatremia, while unresolved hypernatremia significantly increased mortality (HR=1.254), including a durable long-term increased mortality risk for patients with creatinine < 2mg/dL and MELD < 25. Pre-transplant hypernatremia serves as a morbid prognostic indicator for post-transplant morbidity and mortality.