Objective: Long-term quality-of-life (QOL) outcomes, complications and clinical effectiveness in patients undergoing treatment with upper airway surgery (UAS), continuous positive airway pressure (CPAP) and mandibular advancement splints (MAS) for adult obstructive sleep apnoea (OSA). Design: Retrospective cohort study. Setting: Multidisciplinary OSA clinic in University teaching hospital. Participants: Consecutive, simultaneously treated patients with OSA undergoing UAS (n = 83), CPAP (n = 83) and MAS (n = 79). Main outcome measures: Glasgow Benefit Inventory (GBI), Snoring Severity Scale (SSS), Epworth Sleepiness Score (ESS) and side-effects in all three groups were recorded at a mean of 34.5 months following start of treatment and compared via anova with Bonferroni's adjustment for pairwise comparisons. Results: Upper airway surgery demonstrated a statistically significant QOL benefit over MAS. All three groups showed a significant improvement in SSS with CPAP significantly better than MAS, but equivalent to UAS. Uncomplicated UAS provided a greater QOL outcome than compliant MAS, non-compliant CPAP (P < 0.05) and comparable to compliant CPAP. Patients undergoing UAS with recorded complications still reported equivalent QOL outcomes to compliant CPAP and MAS, suggesting these surgical complications are relatively minor compared to the QOL benefit of OSA treatment. Conclusion: Upper airway surgery showed a significant improvement in QOL outcomes compared to non-compliant CPAP or MAS and equivalent benefit to compliant CPAP. This study strongly supports the role for contemporary UAS in OSA when CPAP is not or no longer an option.