Introduction: With the rising prevalence of severe obesity and type 2 diabetes (T2D), bariatric surgery offers a clinical and cost-effective treatment for carefully selected patients. Despite this, the provision of surgical services varies significantly between countries.Objective: To inform health service planning by estimating the number of people who would potentially benefit from bariatric surgery.Setting: Nationally representative sample of community-dwelling older adults.Methods: We applied two separate evidence-based criteria sets for eligibility for bariatric surgery. For the first set of criteria, we considered those with body mass index >= 40 kg/m(2) or >= 35 kg/m2 and one or more of the following: T2D, hypertension, previous myocardial infarction, or sleep apnea. For the second set of criteria, we considered patients with T2D and body mass index >= 35 kg/m2, with one or more of the following: previous myocardial infarction, elevated urine albumin-creatinine ratio, retinopathy, neuropathy, or peripheral vascular disease. Prevalence estimates were applied to census figures for 2011, estimating absolute numbers meeting the criteria.Results: Among adults aged >= 50 years, 7.97% (95% confidence interval [CI]: 7.23, 8.78), representing 92,573 people (95% CI: 83,978, 101,981), met criteria one and 0.97% (95% CI: 0.73, 1.28), representing 11,231 people (95% CI: 8471, 14,890), met criteria two. With fewer than 1/100,000 population publicly funded surgeries taking place annually, current service provision meets much less than 0.1% of the need.Conclusions: While many adults who fulfill the eligibility criteria for bariatric surgery may not want or require it, the current level of need for bariatric surgical services is not being met. A strategy to develop and expand the provision of bariatric care is urgently needed. (C) American Society for Metabolic and Bariatric Surgery. All rights reserved.