Background Comparative international practice of patients undergoing bariatric-metabolic surgery for type 2 diabetes mellitus (T2DM) is unknown. We aimed to ascertain baseline age, sex, body mass index (BMI) and types of operations performed for patients with T2DM submitted to the IFSO Global Registry. Materials and Methods Cross-sectional analysis of patients having primary surgery in 2015–2018 for countries with ≥90% T2DM data completion and ≥ 1000 submitted records. Results Fifteen countries including 11 national registries met the inclusion criteria. The rate of T2DM was 24.2% (99,537 of 411,581 patients, country range 12.0–55.1%) and 77.1% of all patients were women. In every country, patients with T2DM were older than those without T2DM (overall mean age 49.2 [SD 11.4] years vs 41.8 [11.9] years, all p < 0.001). Men were more likely to have T2DM than women, odds ratio (OR) 1.68 (95% CI 1.65–1.71), p < 0.001. Men showed higher rates of T2DM for BMI <35 kg/m2 compared to BMI ≥35.0 kg/m2, OR 2.76 (2.52–3.03), p < 0.001. This was not seen in women, OR 0.78 (0.73–0.83), p < 0.001. Sleeve gastrectomy was the commonest operation overall, but less frequent for patients with T2DM, patients with T2DM 54.9% vs without T2DM 65.8%, OR 0.63 (0.63–0.64), p < 0.001. Twelve out of 15 countries had higher proportions of gastric bypass compared to non-bypass operations for T2DM, OR 1.70 (1.67–1.72), p < 0.001. Conclusion Patients with T2DM had different characteristics to those without T2DM. Older men were more likely to have T2DM, with higher rates of BMI <35 kg/m2 and increased likelihood of food rerouting operations.