Objectives: Brachiobasilic arteriovenous fistulas (BBAVF) can be performed in one or two stages. We compared primary failure rates, as well as primary and secondary patency rates of one- and two-stage BBAVF at two institutions. Methods: Patients undergoing one- and two-stage BBAVF at two institutions were compared retrospectively with respect to age, sex, body mass index, use of preoperative venous duplex ultrasound, diabetes, hypertension, and cause of end-stage renal disease. Categorical variables were compared using chi-square and Fisher's exact test, whereas the Wilcoxon rank-sum test was used to compare continuous variables. Patency rates were assessed using the Kaplan-Meier survival analysis and the Cox proportional hazards model with propensity analysis to determine hazard ratios. Results: Ninety patients (60 one-stage and 30 two-stage) were identified. Mean follow-up was 14.2 months and the mean time interval between the first and second stage was 11.2 weeks. Although no significant difference in early failure existed (one-stage, 22.9% vs two-stage, 9.1%; P = .20), the two-stage BBAVF showed significantly improved primary functional patency at 1 year at 88% vs 61% (P = .047) (hazard ratio, 0.2 (95% confidence interval [CI], .04.80; P = .03). Patency for one-stage BBAVF markedly decreased to 34% at 2 years compared with 88% for the two-stage procedure (P = .047). Median primary functional patency for one-stage BBAVF was 31 weeks (interquartile range [IQR], 1154) vs 79 weeks (IQR, 29131 weeks) for the two-stage procedure, respectively (P = .0015). Two-year secondary functional patency for one- and two-stage procedures were 41% and 94%, respectively (P = .015). Conclusions: Primary and secondary patency at 1 and 2 years as well as functional patency is improved with the two-stage BBAVF when compared with the one-stage procedure. Lower primary failure rates prior to dialysis with the two-stage procedure approached, but did not reach statistical significance. While reasons for these finding are unclear, certain technical aspects of the procedure may play a role.