Adrenal cysts are rare. Most are benign but some may contain malignancy. There are no established guidelines for their surgical management. The purpose of this study was to determine the pathological findings and likelihood of malignancy in hormonally inactive adrenal cysts after adrenalectomy. Using the pathology registries at two centers, we identified patients who underwent excision of an adrenal cyst between 1994 and 2009. Hormonally active cysts including pheochromocytomas were excluded. Charts were reviewed for patient demographics, presentation, surgical management, and postoperative course. Of 551 adrenalectomy specimens, 15 (2.7%) contained an inactive adrenal cyst or cystic component. Cysts were more likely to be in women (67%) and right-sided (73%). Three patients (20%) were symptomatic from their lesion. Laparoscopic adrenalectomy was performed in nine patients (60%). Pathology revealed eight hemorrhagic cysts, four lymphangiomas, one hemangioma, one epithelial cyst, and one metastatic pulmonary adenocarcinoma. Laboratory and radiographic workup are essential in determining whether adrenal cysts have hormonal function or a solid tissue component before adrenalectomy. Although nonfunctional adrenal cysts may contain malignancy, most are benign. It is reasonable to observe asymptomatic, nonfunctioning, benign-appearing adrenal cysts in patients in whom follow-up can be ensured.