Objective: Chronic kidney disease and renal failure are common in patients being considered for left ventricular assist device support. We sought to evaluate the outcomes of patients undergoing left ventricular assist device implantation with preoperative dialysis and those with new-onset postoperative renal failure requiring dialysis. Methods: All patients (n = 14,090) undergoing primary left ventricular assist device implantation who were listed in the Interagency Registry for Mechanically Assisted Circulatory Support database (2014-2019) were evaluated. Landmark analysis then stratified patients alive at 1 month by preoperative dialysis and at 1 month postoperatively, preoperative dialysis only, postoperative dialysis only, and no dialysis. Results: Of 14,090 patients undergoing left ventricular assist device implantation, patients on dialysis (400%, 3%) preoperatively had significantly higher mortality at 1 month (18% vs 6%, P < .0001). However, of patients on preoperative dialysis, 131 (32.8%) no longer required dialysis at 1 month postoperatively and had long-term survival similar to patients who never required dialysis (no dialysis vs recovered, P = .13). Long-term survival was significantly worse in patients with persistent dialysis and new dialysis at 1 month postoperatively (P < .0001). Time to first stroke, major nondevice infection, any bleeding event, and gastrointestinal bleeding were all worse in patients on preoperative or postoperative dialysis (all P < .0001). Device infection, malfunction, or thrombosis was not associated with dialysis status (P > .05). Negative predictors of recovery include biventricular assist device (odds ratio, 0.20) and inotropes 1 week postimplant (odds ratio, 0.19). Conclusions: Preoperative renal failure is associated with 3 times higher mortality and worse morbidity in patients receiving a left ventricular assist device. However, one-third of patients with preoperative dialysis will recover renal function postimplant with similar long-term survival and quality of life as those without dialysis.