Purpose The research aims to provide empirical evidence on the relationship between financial statement comparability (FSC) and cost of equity (COE) in an emerging market. Design/methodology/approach Specifically, this study examines the relationship between FSC and COE of Vietnamese listed firms. The research uses the System Generalized Method of Moments regression techniques for a panel data set of 454 companies for the period 2015–2022. Findings The authors find that firms with high comparability of financial statements have lower COE. To confirm the research findings, the authors conduct the robustness test by using different proxies for the cost of equity. Consistent results are found. Originality/value The study contributes to the overall understanding of the relationship between FSC and COE, and suggests policy implications for relevant stakeholders such as managers, regulatory bodies and investors. Especially, regarding policymakers, this study could provide more insight into how the accounting convergence process impacts the effectiveness of a firm’s capital allocation.