Food banks have become increasingly central to addressing food insecurity, but face ongoing challenges in maintaining sustainable operations due to fluctuating and limited food donations. Demonstrating their long-term impact plays a role in sustaining support and funding. However, current evaluation approaches often lack coherence, consistency, and contextual sensitivity, limiting their value in guiding the development of resilient food assistance infrastructure. This study aims to identify key elements essential for developing a comprehensive framework for evaluating the impact of food banks by consolidating evidence from existing literature. Relevant literature was systematically identified and mapped using PRISMA-ScR guidelines, ensuring a rigorous and transparent approach to capturing key themes and evidence. Findings reveal two main outcome areas for evaluating food banks: beneficiary-focused outcomes, which span nutrition and health, social, and economic domains, and systems-focused outcomes, with food waste reduction emerging as a predominant area of focus. Recurring evaluation challenges include the limitations of self-reported data, variation in program delivery, and insufficient integration of broader service contexts. These challenges highlight the need for evaluations grounded in clearly defined purposes and outcome measures, supported by a systems perspective that accounts for external influences. This study also emphasises the value of mixed-method approaches and adaptable tools that reflect diverse operational contexts. By addressing critical gaps and proposing core design requirements, this study offers a foundation for more coherent and actionable evaluation frameworks. Strengthening evaluation practices helps demonstrate long-term impact, contributes to the operational resilience of food banks, and supports their integration into sustainable food assistance infrastructure.