Purpose Gastropleural and gastrobronchial fistulas (GPF/GBFs) are serious but rare complications after bariatric surgery whose management is not consensual. The aim was to establish a cohort and evaluate different clinical presentations and therapeutic options. Materials and Methods A multicenter and retrospective study analyzing GPF/GBFs after bariatric surgery in France between 2007 and 2018, via a questionnaire sent to digestive and thoracic surgery departments. Results The study included 24 patients from 9 surgical departments after initial bariatric surgery (21 sleeve gastrectomies; 3 gastric bypass) for morbid obesity (mean BMI = 42 ± 8 kg/m2). The GPF/GBFs occurred, on average, 124 days after bariatric surgery, complicating an initial post-operative gastric fistula (POGF) in 66% of cases. Endoscopic digestive treatment was performed in 79% of cases (n = 19) associated in 25% of cases (n = 6) with thoracic endoscopy. Surgical treatment was performed in 83% of cases (n = 20): thoracic surgery (n = 5), digestive surgery (n = 8), and combined surgery (n = 7). No patient died. Overall morbidity was 42%. The overall success rate of the initial and secondary strategies was 58.5% and 90%, respectively. The average healing time was approximately 7 months. Patients who had undergone thoracic surgery (n = 12) had more initial management failures (n = 9/12) than patients who had not (n = 3/12), p = 0.001. Conclusion Complex and life-threatening fistulas that are revealed late require a multidisciplinary strategy. Thoracic surgery should be reserved once the abdominal leak heals; otherwise, it is associated with a higher risk of failure.