PurposeThe study aims to delve into the interactive relationships among brand authenticity, brand attachment, brand trust and brand loyalty using the ERC authenticity framework, exploring the potential mechanisms and different configurations affecting brand loyalty through brand authenticity.Design/methodology/approachAbout 446 valid samples were collected through an online survey of Chinese consumers of international sports brands. Structural equation modeling (SEM) and fuzzy set qualitative comparative analysis (fsQCA) were employed to test the research hypotheses.FindingsSEM results indicate significant positive correlations among brand true-to-ideal authenticity, true-to-fact authenticity and true-to-self authenticity. All dimensions of brand authenticity exert notable positive impacts on brand attachment, brand trust and brand loyalty. Brand true-to-ideal authenticity, true-to-fact authenticity and true-to-self authenticity not only directly influence consumer brand loyalty but also indirectly affect it through brand attachment and brand trust; fsQCA results reveal five heterogeneous configurations to predict brand loyalty.Originality/valueThis study not only uses SEM to validate the structural relationships among the three dimensions of brand authenticity and their linear relationships with brand attachment, brand trust and brand loyalty but also uses fsQCA to identify nonlinear relationships between concepts. It extends complexity theory to the research field of brand authenticity–brand loyalty. Furthermore, based on the research results, this study provides management suggestions for brand managers and marketers.