BACKGROUND: Malnutrition in infants aged <6 mo (u6m) is poorly identified and managed in many countries, increasing the risk of poor growth and development. Addressing this gap, 2023 WHO malnutrition guidelines recommend assessment, classification and treatment at primary care level. This study aimed to assess primary healthcare facility readiness for nutritional care in infants u6m. METHODS: We adapted the Harmonized Health Facility Assessment (HHFA), adding items for Management of small and nutritionally At-risk Infants u6m and their Mothers (MAMI) at five care contact points. Our HHFA-MAMI tool captured 342 items using healthcare provider interviews, observations and registers data to calculate mean scores per area and median patient visits. RESULTS: We surveyed 15 facilities in Senegal. General readiness scored 69.5%, MAMI availability and readiness 37.7%. Infrastructure (72.0%) and health workforce (60.7%) were available, while equipment (32.5%) and training (22.3%) scored low. Infants were frequently assessed (53.6%), not often classified (15.2%) as at risk, nor adequately treated (38.2%). Comparing contact points, delivery and sick child clinic scored highest in readiness, immunization in utilization. CONCLUSIONS: Primary care readiness gaps exist in classifying and treating at-risk infants u6m, equipment and training. We found opportunities at each of the five contact points to implement WHO-recommended care.