OBJECTIVES: We used 2 multi-attribute utility instruments (MAUIs) to assess short-term quality-of-life impacts for a unique cohort of long-term waitlisted patients for bariatric surgery immediately before and 3 months after surgery. We were provided with a novel opportunity to investigate the short-term health impacts for a special cohort of severely/super-obese long-term waitlisted patients who were prioritised for bariatric surgery through a targeted allocation of public funds to reduce waiting lists. METHODS: Participants (n=16) completed the EQ-5D-5L and AQoL-8D MAUIs immediately before and 3 months after bariatric surgery. We compared summary health state utility values (HSUVs) and individual/super-dimension scores (AQoL-8D) and dimension-to-dimension analyses (both instruments) to investigate patients’ quality-of-life changes and the MAUIs’ discriminatory attributes. RESULTS: Mean (SD) total weight loss was 9.5% (5.5%). HSUV measured by both instruments improved after surgery (EQ-5D-5L: 0.66 (0.26) to 0.73 (0.23)) and (AQoL-8D: 0.53 (0.24) to 0.63 (0.24)). Despite improvements from baseline, post-surgery HSUVs did not substantially approach population norms nor did nine of the ten AQoL-8D individual/super-dimension scores of Independent Living, Senses, Pain, Coping, Self-worth, Relationships, Mental-health, Mental and Physical super-dimensions. In contrast, ‘Happiness’ improved the most and approached levels seen in the general population. CONCLUSIONS: MAUI HSUVs and individual/super-dimensions revealed that physical and psychosocial health was significantly diminished before surgery and that there were short term post-operative improvements. The AQoL-8D provided a more detailed understanding of the impacts on individual domains of health. In turn, these findings could support clinicians’ pre/postoperative assessment and inform resource planning for clinical and allied healthcare follow-up.