INTRODUCTION: A lack of rigorous, objective measurement of health promotion (HP) in sports clubs has been identified. This study developed and validated content of an observational tool for sports managers to evaluate HP within their clubs. METHODS: First, a rapid literature review identified sports club HP observational tools and their development process. Second, a 3-round Delphi study gathered feedback from 69 sports stakeholders to design a checklist. Round 1 created items and observation areas; Round 2 obtained feedback, item suggestions and reformulations; Round 3 structured items into a checklist and rated them on three indicators. Third, experts categorized items into health determinants from the health promoting sports club (HPSC) model and drafted a user's guide. RESULTS: The rapid review yielded 11 studies, including tools for injury surveillance, coaching behaviours, alcohol management, referee-athlete interaction and motivation, but none directed at HP. The Delphi study round 1 included 18 respondents formulating 24 items organized into: Locker room, Website, Cafeteria & Food Offerings and Facilities & Surroundings. Round 2 included 31 respondents validating 43 items and reformulating 'Locker room' into 'Locker and Restrooms'. Round 3 included 21 respondents validating 36 items separated into the four areas. Five researchers categorized items into Economic (n=5), Environmental (n=16), Organizational (n=17) and Social (n=9) health determinants. The HPSC Observational Tool includes a user's guide, a checklist including scoring methods and recommendations. CONCLUSION: This study provides an innovative observational tool for sports managers to assess their club's HP. Sports managers can directly evaluate specific areas and follow recommendations for improvement.