This research reveals the effect of corporate social responsibility (CSR) reporting on sustainability performance (SP). Moreover, the study investigates the moderating role of board financial expertise (BFEX) between CSR reporting and the SP on the Saudi Arabian Exchange. The study used a database of 469 observations from non-financial companies on the Saudi market from 2017 to 2023, using fixed effect models to estimate the study results. The study findings indicate that CSR reporting enhances SP in the long term. The companies that have CSR reporting are associated with higher SP. Furthermore, the results reveal that BFEX moderates the nexus between CSR reporting and SP. The study's originality lies in its exploration of the moderating role of BFEX on the association between CSR reporting and SP by using a sample from Saudi companies. This research offers practical insights for companies, policymakers, and stakeholders to enhance SP. The study provides actionable insights for companies to align CSR reporting with sustainability practices, enhancing their SP.