To characterize adverse events, provide a safety profile, and understand patient outcomes after complications arising from LigaSure and Harmonic use in the head and neck region. Retrospective analysis of adverse events from the Manufacturer and User Facility Device Experience (MAUDE) between January 2013 and 2023. A total of 158 LigaSure and 159 Harmonic events were extracted. There were significantly more reports of Harmonic device overheating (6.9% vs. 0.6%, p = 0.003) and spontaneous self-activation (4.4% vs. 0%, p = 0.032). Although intra-operative and post-operative complications were similar among both groups, there were significantly more intra-operative bleeding events for LigaSure as compared to Harmonic (8.2% vs. 0.0%, p = 0.001). Understanding technical complications and adverse events attributable to LigaSure and Harmonic devices enables the development of clinically relevant risk mitigation strategies. Surgeons should avoid improper use by remaining vigilant of device functionality and temperature changes.