This paper investigates the impact of the Shanghai–Hong Kong Stock Connect (SHSC) scheme on voluntary corporate social responsibility (CSR) disclosure in China. Using a difference-in-differences (DiD) design, we find that companies that participate in the SHSC scheme are more inclined to voluntarily issue CSR reports. This effect is more pronounced for companies that have limited access to international markets and those with weak corporate governance. Additional analyses show that SHSC-connected firms also produce higher quality CSR reports and achieve a better CSR performance. Our findings imply that capital market liberalisation promotes voluntary corporate disclosure for investors.