Purpose: Complications associated with retroperitoneal lymph node dissection (RPLND) have primarily been described from single-center data. These historical single-center studies often lack standardized reporting preventing combined cohort analysis. Therefore, we describe and discuss the complications associated with RPLND from a prospectively maintained, validated, national database. Materials and Methods: The National Surgical Quality Improvement Program (NSQIP) database was queried for 30-day postoperative complications following RPLND for testicular cancer from 2005–2018, which comprised the cohort for analysis. Complications were subcategorized by organ systems and by Clavien-Dindo classification grade (I–II [low], III–V [high]). A subanalysis of large (>5 cm) retroperitoneal masses was evaluated as a surrogate for postchemotherapy RPLND. Associations with patient and perioperative variables were analyzed with logistic regression. Results: A total of 375 patients met inclusion criteria. Seventy-four patients (19.7%) experienced at least one postoperative complication for a total of 125 complications. The median hospital length of stay was 5 (interquartile range, 4–7) days. Hospital readmission occured in 32 patients (8.5%). There were 52 patients (13.9%) who underwent RPLND for large masses, with a 34.6% complication rate. The most common organ system complications included blood transfusions (11.7%), wound dehiscence/infection (4%), and pulmonary (2.3%). The majority of complications were of low Clavien-Dindo classification grade (12% vs. 3.5%). On univariable analysis, smoking, disseminated cancer, steroid use, older age, low albumin, low hematocrit, low platelet counts, and longer operative times were significantly associated with the occurrence of any complication. Smoking, low hematocrit, and longer operative times remained significant on multivariable analysis. Conclusion In the NSQIP database, complication rates following RPLND are predominantly of low Clavien-Dindo classification grade and are higher than some previously published single-center series. Increased rates were associated with smoking, unfavorable preoperative blood counts, and longer operative times.