Background: During the last few years, many surgeons have begun to utilize the LigaSure device or Harmonic scalpel to perform thyroid surgery. Several papers have demonstrated the benefits of these devices compared with traditional hand-tying techniques. The purpose of this study was to examine our institution's experience with the LigaSure device and Harmonic scalpel during thyroid surgery and to compare mean operative times and complications associated with each device. Methods: A retrospective chart review was performed on all patients who underwent thyroid surgery using the LigaSure device or Harmonic scalpel at a single institution between December 2005 and August 2009. Charts were reviewed for patient demographics, mean operative time, length of stay, and complications, such as transient recurrent laryngeal nerve injury, hypocalcemia, and hematoma formation. Results: A total of 231 patients were included in the study, of whom 123 underwent total thyroidectomy and 108 underwent lobectomy. There was a significant decrease in the operative time for both thyroidectomies and lobectomies when the Harmonic scalpel was utilized. In regard to complications, there was no statistically significant difference in the number of transient and permanent recurrent laryngeal nerve injuries, percentage of patients developing hypocalcemia, or rate of hematoma development. Conclusion: In this study, there was no difference in the rate of complications between the two devices. However, the use of the Harmonic scalpel significantly decreased operative time for both thyroidectomies and thyroid lobectomies compared with the LigaSure device. © 2010 Society of Surgical Oncology.