AimsThis study aimed to explore the multidisciplinary team attitudes and knowledge of bariatric surgery micronutrient management (pre‐ and postoperative care) and to evaluate the implementation of an extended‐scope of practice dietitian‐led model of care for micronutrient monitoring and management.MethodsA mixed method study design included quantitative evaluation of micronutrient testing practices and deficiency rates. Qualitative reflexive thematic analysis was used to interpret multidisciplinary experience with micronutrient monitoring in a traditional and dietitian‐led model of care. In addition, deductive analysis used normalisation process theory mapping of multidisciplinary experience with the implementation of the dietitian‐led model of care.ResultsIn the traditional model, a lack of quality evidence to guide micronutrient management, and a tension in trust between surgeons and patients related to adherence to micronutrient prescriptions were described as challenges in current practice. The dietitian‐led model was seen to overcome some of these challenges, increasing collaborative, and coordinated, consistent and personalised patient care that led to increased testing for and detection of micronutrient deficiencies. Barriers to sustainability of the dietitian‐led model included a lack of workforce succession planning, and no clearly defined delegation for some aspects of care.ConclusionAn extended scope dietitian‐led model of care for micronutrient management after bariatric surgery improves clinical care. Challenges such as succession planning must be considered in design of extended scope services.