Objectives/Hypothesis During robot‐assisted transaxillary thyroidectomy, the patient's arm is maintained in an overhead flexed position for a prolonged time, which poses a risk of postoperative brachial plexopathy. The aim of the study was to identify the causes of brachial plexopathy and to assess the benefit of intraoperative neurophysiological monitoring (IONM) in preventing positional brachial plexopathy in this setting. Study Design Retrospective case series. Methods The computerized database of a tertiary medical center was searched for all consecutive patients who underwent robot‐assisted transaxillary thyroidectomy between 2012 and 2014. Clinical, operative, and outcome parameters were collected from the medical files. Findings were compared between patients operated with and without IONM. Results The cohort included 30 patients, 14 operated with IONM and 16 without. Three events of impending brachial plexopathy were detected in the monitored group. The monitored group had significantly better shoulder movement (P = .003), a lower rate of hypoesthesia (P = .011), less pain (P = .001) in the early postoperative period than the nonmonitored group and higher quality of life in the early postoperative period (P = .012). The monitored group was significantly younger than the nonmonitored one (P = .02) and had a significantly larger diameter of thyroid nodule than the nonmonitored group (P = .043). Conclusions IONM during robot‐assisted transaxillary thyroidectomy may improve short‐term postoperative pain and shoulder movement and longer‐term quality of life. Level of Evidence 4 Laryngoscope, 126:2187–2193, 2016