Purpose – This paper provides insights into the applicability of excellence models (in particular the European Foundation for Quality Management (EFQM) Excellence Model), for use in the nonprofit context as a strategy for performance improvement aiming to enhance sustainability. Design/methodology/approach – The study is based on an exploratory, qualitative in-depth case study approach, which includes three UK-based nonprofit organizations (NPOs) as research case studies. Findings – In general, we found the quality models to be relevant to the NPO context, and potentially effective and useful as a performance improvement strategy for NPOs. However, we also propose some modifications to the EFQM model to address the specific characteristics of this sector. Additionally, we compare two of the most widely used quality models (EFQM and MBNQA), and suggest that although both are relevant for NPOs, the EFQM model has some superior advantages. Originality/value – This paper contributes to the debate about the sustainability of organizations and the underpinning mechanisms behind their efficiency. Many researchers and practitioners are continually debating how an organization can optimize its available resources, as this is considered to be one of the primary foundations for organization sustainability. The added contribution of this paper advances this debate a step further by providing insights into how concepts and tools which have been initially designed for the for-profit sector can be deployed by nonprofit organizations (NPOs). In addition, the paper provides further views about the approaches NPOs might use in response to the current political and financial challenges.