BACKGROUNDS: Accounting for geographical factors is essential when studying patient care pathways, assessing disease prevalence, and analysing social and territorial inequalities in health. Breaking down health data by geographic areas is therefore a crucial issue for public policy and health management at the local level. However, the characteristics of the geographic information used in the analysis of health data from the French National Health Data System (SNDS) remains poorly documented in studies and largely absent from publications. METHODS: A group of experts from the RedSiam network's task force on methodology explored the multiple geographical dimensions within the SNDS (place of residence, place of care, place of death, etc.) by conducting a documentary and technical analysis of its main health administrative databases RESULTS: This collective expertise highlights the challenges associated with the spatialisation of health data, both in terms of quality and reliability. Correction methods and standardisation tools are provided to enhance the use of geographic data and to help users understand their limitations. In addition, the task force's findings have been summarised from a decision-support perspective to guide SNDS users in selecting the geographic information best suited to their objectives in epidemiology or health services research. CONCLUSIONS: This work offers a valuable methodological framework for researchers and analysts who incorporate territorial aspects into their public health analyses.