AIM: This scoping review aimed to identify and appraise the effectiveness and impact of breastfeeding promotion interventions conducted across Portuguese-speaking sovereign countries. METHODS: Using the PRISMA-ScR guidelines, we searched 14 electronic databases for publications published through 31 July 2023. The search terms were designed to find studies promoting breastfeeding or exclusive breastfeeding in pre-defined Portuguese-speaking countries. RESULTS: Of the 5263 papers initially retrieved, 30 interventional studies on breastfeeding met the inclusion criteria across three countries: Brazil (N = 26), Portugal (N = 2) and Guinea Bissau (N = 2). Participants ranged from pregnant women, mothers, mother-infant pairs, healthcare professionals, and school children. Overall, the interventions increased exclusive breastfeeding and better breastfeeding practices, such as a higher duration of breastfeeding. The interventions positively affected maternal breastfeeding self-efficacy, knowledge and perception. Only four studies used a theoretical framework. CONCLUSION: While the results were often statistically significant, no study had an outcome close to the recommended UNICEF and WHO goal of 70% breastfeeding at six months. The need to determine what works for the recommended six months postpartum period is critical for maximising children's health in Portuguese-speaking countries.