PurposeDespite their significant economic impact, small and medium-sized enterprises (SMEs) remain underrepresented in public procurement. While previous research has identified the barriers facing SMEs in public procurement markets, a knowledge gap still exists on how these barriers influence one another in a specific context.Design/methodology/approachThis study developed a hierarchical structural model that reveals the contextual interrelationships between 14 notable barriers to SME involvement in public procurement, based on evidence from the publicly funded healthcare sector in the UK. The data were analyzed using interpretive structural modeling (ISM) and matrix impact of cross-multiplication applied to categorization (MICMAC).FindingsThe results systematically classify barriers based on their hierarchical relationships, offering a robust theoretical foundation for understanding their nature and interconnections.Practical implicationsThe findings can help scholars, government administrators and politicians in government-funded healthcare systems determine the most influential barriers to SME involvement and their causes, enabling them to build viable remedies.Originality/valueThis is the first empirical study to examine the relationship between the barriers to SMEs' public health procurement, using evidence from the public health procurement context.