Health Impact Assessment (HIA) is a proactive, evidence-based approach that integrates health considerations into decision-making across sectors to prevent adverse effects and promote health equity. While global interest in HIA is growing, its implementation varies by country. In Portugal, despite existing legal frameworks and some previous capacity-building efforts, HIA is not fully institutionalized, and its practice within the Public Health System (PHS) remains largely undocumented. To address this, we conducted an online survey targeting regional and local PHS professionals to assess their awareness, experience, and perceptions of the barriers and facilitators to effective HIA implementation. The results obtained from 187 valid answers gathered from the survey revealed a strikingly low level of HIA awareness and practice within the Portuguese PHS, underscoring the urgent need for improved training and capacity building. Furthermore, the survey identified strong professional interest in HIA initiatives, suggesting significant potential for developing HIA specialized educational programs. Overall, the findings call for stronger political leadership at the governmental level to establish HIA as a key tool for achieving sustainable development goals. Finally, the study emphasizes the potential for international collaboration, particularly with Portuguese-speaking countries, to adapt these insights to their own contexts.