["Corporate Social Responsibility and Environmental Management, Volume 33, Issue 4, Page 4725-4743, July 2026. ", "\nABSTRACT\nWithin the framework of sustainable development and environmental policy, environmental certification is regarded as a mechanism through which road passenger transport companies (RPTCs) could mitigate their adverse environmental impacts and attain competitive advantages that may enhance their financial performance. The objective of this study is to analyse whether the financial performance of RPTCs improves as a result of the influence that environmental certification exerts on passengers' perceived image, sustainable asset management and employees' environmental behaviour. Using panel data covering the period 2010–2019, a comparative analysis was conducted between certified and non‐certified RPTCs, focusing on the routes they operate and their affiliation status. While the effect of certification on sustainable asset management strengthens financial performance, the improvement in passengers' environmental image has only a partial effect. Conversely, the influence of certification on employees' environmental behaviour has been found to exert a negative impact on financial performance.\n"]