Robot-assisted transaxillary thyroidectomy (RATT) is an emerging technique with excellent cosmetic results but is supposedly more invasive and painful than conventional thyroidectomy (CT). This prospective study compared pain after RATT and CT.Inclusion criteria were a nodule <5 cm and volume <30 mL. Patients received the same analgesia. Pain was evaluated by visual analog scale (VAS) in the recovery room (VASrr), on the first postoperative day at 8:00 a.m. (VAS 8 a.m.) and 8:00 p.m. (VAS 8 p.m.), at 8:00 a.m. on the second postoperative day (VAS 8*a.m.), and after 7 days (VAS 7). Operative time and complications were evaluated.From May 2015 to September 2015, 124 patients (all women) underwent thyroidectomy: 62 underwent RATT and 62 underwent CT. Mean age was 39.7 ± 10.2 years in the RATT group and 41.4 ± 12.5 years in the CT group. Groups were comparable for thyroid volume and nodule diameter. Operative time was longer in the RATT group than in the CT group (119.4 ± 25.5 versus 70.3 ± 11.0 minutes). Complications were three transient hypocalcemia in RATT and four in the CT group. No definitive complications occurred. VASrr was lower in the RATT group (1.79 ± 2.06 versus 2.5 ± 1.18; P < .0001). There was no difference between groups for VAS 8 a.m., VAS 8 p.m., and VAS 8*a.m., but VAS 7 was higher in the RATT group (0.85 ± 1.77 versus 0.17 ± 0.52; P < .010).RATT is as safe and effective as CT. Patients undergoing RATT, surprisingly, experienced less pain in the immediate postoperative period. However, the VAS 7 score was higher in the RATT group, probably because the intact neck is favorable in the early phase of recovery, but the large dissection takes longer for healing.