Objective To report on 30-day adverse event rates and timing of complications following adrenal surgery; further, to investigate the impact of specialty (general surgery vs urology) on these outcomes using a large prospective multi-institutional data registry. Materials and Methods Within the American College of Surgeons National Surgical Quality Improvement Program (2005-2012), patients undergoing adrenalectomy were identified (CPT-codes: 60540, 60545, 60650). Outcomes evaluated included complications, blood transfusion, length of stay, reintervention, readmission, and mortality. Complications were further evaluated in relation to discharge status (pre-/postdischarge). Multivariable regression models assessed association between specialty and 30-day morbidity/mortality. Results During the study period, 4844 patients underwent adrenalectomy (95.7% general surgery). The overall complication rate was 7.5% (n = 363); 43.2% of the complications occurred postdischarge with a substantial proportion of major complications, including cardiac, pulmonary, renal, neurologic, septic, and deep venous thrombosis/pulmonary embolism also occurring postdischarge (29.9%). The overall blood transfusion, reintervention, readmission, and mortality rates were 3.9%, 2.0%, 6.4%, and 0.6%, respectively. In adjusted analyses, specialty did not have an effect on any of the outcomes (P > .05 all). Conclusion One in 13 patients suffers a complication postadrenalectomy. Approximately 40% of these complications occur postdischarge, primarily within the first 2 weeks of surgery. Accurate knowledge regarding 30-day adverse event rates and timing of complications that this study provides may facilitate improved patient-physician communication and encourage early patient follow-up in this critical window. Lastly, specialty does not seem to affect outcomes in American College of Surgeons National Surgical Quality Improvement Program participant hospitals.