AbstractBackgroundCurrently, limited data exist as to long‐term disease‐specific outcomes after endoscopic sinus surgery (ESS) for chronic rhinosinusitis (CRS). In this report, we present outcomes data collected over 5 years in a large prospective cohort of patients who underwent surgical treatment for CRS.MethodsPatients who completed the 22‐item Sino‐Nasal Outcome Test (SNOT‐22) before ESS were asked to complete the same survey at yearly intervals for 5 years thereafter. The impact of patients’ demographics and clinical characteristics on clinical outcome was measured using mixed effects modeling for univariate and multivariable analysis. Multivariable logistic regression threshold analyses were also performed.ResultsAmong the 925 patients enrolled in the study, the SNOT‐22 was completed after ESS by 641 patients (69.3%) at 1 year and 338 patients (36.5%) at 5 years. The mean preoperative SNOT‐22 score of 48.5 (standard error [SE], 0.69) improved at all subsequent yearly time‐points, including 5 years (mean, 25.8; SE, 1.08; p < 0.0001). SNOT‐22 scores over time were impacted by nasal polyps (p < 0.001), environmental allergies (p = 0.010), diabetes (p = 0.032), and preoperative Lund‐Mackay score (p < 0.001).ConclusionEndoscopic sinus surgery appears to be effective at improving the quality of life of patients with CRS for both the short and long term. The successful outcome of such surgery, however, is influenced by a variety of clinical factors, which should be taken into account by clinicians who are considering surgical treatment of CRS for select patients.