The rapid spread of SARS-CoV-2 has posed unexpected and emergency challenges to humanity for which no country, health system or institution was prepared. If in a normal context the effectiveness of a healthcare team is extremely important for the quality of the services provided, in the context of a pandemic this factor becomes even more important for users and for the sustainability of the Portuguese National Health Service. The aim of this study is to analyze how leadership contributes to nursing team effectiveness when mediated by job satisfaction, organizational trust and commitment, and moderated by employee self-rated health in a Northern Portuguese Primary Health Care Organization (PHCO). A quantitative study was carried out by applying a questionnaire to all the nurses in an PHCO. 207 valid responses were obtained (87.7% response rate). The proposed model was tested using the structural equation modeling technique. The results indicate that: i) leadership positively influences job satisfaction, commitment (to the leader), organizational trust and team effectiveness; ii) team effectiveness is influenced by job satisfaction and organizational trust; iii) commitment (to the leader) had no significant effect on team effectiveness. This study provides insights into the relationships between leadership and team effectiveness in PHCO settings and is anticipated to inform future interventions aimed at improving team performance.