Following the previous national prevalence survey (ENP) Prev'Ehpad 2016, a new ENP on healthcare-associated infections (HAIs) and antimicrobial treatments (AMT) in long-term care facilities for the elderly (Ehpad) will be conducted in May–June 2024. This 2024 NPS in Ehpad facilities represents a key milestone in the surveillance and prevention of healthcare-associated infections, antibiotic resistance, and the appropriate use of antibiotics. The 2024 National Prevalence Survey is being conducted as part of the European HAI-Net HALT-4 project of the European Centre for Disease Prevention and Control (ECDC) and coordinated at the national level by Santé publique France. It is led by the Network for the Prevention of Healthcare-Associated Infections (RéPias) and carried out in collaboration with the Support Centers for the Prevention of Healthcare-Associated Infections (CPias). The 2024 National Prevalence Survey aims to produce benchmark indicators at the national and regional levels, in the form of measurements of the prevalence of healthcare-associated infections and antimicrobial treatments in long-term care facilities, to guide and evaluate national and regional policies on infection prevention and antimicrobial resistance. It also contributes to providing French data for the European survey coordinated by the ECDC. The survey further aims to raise awareness and mobilize all healthcare professionals in long-term care facilities involved in the prevention and control of healthcare-associated infections, the appropriate use of antibiotics, and the fight against antibiotic resistance. It thus provides insights to improve the measures to be implemented in their facilities to prevent infection risk. This guide, intended primarily for investigators of the National Prevalence Survey in nursing homes and their management, provides a standardized tool for conducting the survey. It outlines: 1) the methodological changes for this survey in 2024, covering developments regarding the targeted facilities, data collection procedures, and the variables to be documented. This survey is open to all targeted facilities that volunteer to participate; 2) the organization of the survey in terms of facility participation, data collection and entry, and the composition and distribution of roles within the survey team at each facility. The PrevIAS application, designed for prevalence surveys of healthcare-associated infections (HAIs) and antimicrobial treatments, is made available to facilities for data entry and the reporting of results for each participating facility; 3) the definition of variables and their coding for completing the “facility” and “resident” questionnaires. The sites of healthcare-associated infections and the targeted antimicrobial treatments have been updated for the purposes of this survey. The quality of the indicators produced as part of this survey depends largely on the participation and the quality of the data collected by the facilities.