Objective: To describe changes in disease-specific and global quality of life (QOL) for adults with recurrent or chronic tonsillitis at 6 months and 1 year after tonsillectomy using two instruments: the Tonsil and Adenoid Health Status Instrument (TAHSI) and the SF-12 Health Survey (12-item short form of SF-36 Health Survey). Study Design and Setting: Multicenter, prospective observational outcomes study. Results: Seventy-two adults, mean age 28.0 years (SD 7.2 years), were enrolled with follow-up available for 42 adults at 6 months and for 40 adults at 1 year. Patients showed significant improvements in all six subscales of the TAHSI: airway and breathing, infection, health care utilization, cost of care, eating and swallowing, and behavior (all P < 0.0001). Significant improvements were also found in the physical functioning subscale of the SF-12 at 1 year. Conclusion: After tonsillectomy for recurrent and chronic tonsillitis, we found large improvements in disease-specific and global QOL. Significance: Most prior studies on tonsillectomy for recurrent tonsillitis have assessed only the frequency of infections as an outcome measure. This study describes the changes in QOL measured in our cohort of reporting adults after tonsillectomy for chronic or recurrent tonsillitis. This study provides prospective evidence of the effectiveness of tonsillectomy on adult QOL.