In today’s business environment with fast growing communication and information technologies, knowledge management (KM) capabilities are a valuable source for innovation. However, little is known about the particular KM capabilities that lead to business model innovation (BMI) and whether their effect is dependent upon the firm’s orientation towards risk-taking. We examine the impact internal and external KM capabilities have on BMI and how these effects are moderated by its risk-taking tolerance. We empirically analyze a sample of 197 small and medium-sized enterprises (SMEs) applying structural equation modeling (SEM) and fuzzy-set qualitative comparative analysis (fsQCA). The results from the SEM indicate that particularly external KM capabilities stimulate BMI. This relationship is strengthened for firms with a high risk-taking tolerance. Internal knowledge is only effective for firms with a low risk-taking tolerance. The fsQCA results substantiate these findings and refine the SEM by providing particular antecedent conditions for high levels of BMI.