The integration of online platforms into the real estate market offers a valuable context to explore how online information shapes consumer behaviour and decision-making. This study analyses judicial auction housing transactions across 14 Chinese cities from June 2016 to February 2023, examining the mechanisms through which online information influences transaction outcomes. Empirical results reveal that online information impacts the success probability, auction prices, and discount rates of judicial auction properties by altering buyers’ demand behaviour and pricing decisions. In the search phase, static visual information (e.g., photos) primarily attracts initial interest, while textual details and offline service links convert potential demand into actual participation. In the bidding phase, consumers rely more on a combination of online information (including videos and detailed files) and offline services to inform their decisions. Notably, in the post-pandemic era, the influence of online information on consumer behaviour and price decisions has intensified. These findings provide implications for real estate professionals and policymakers, highlighting the need to enhance information disclosure practices and supervision mechanisms for digital real estate platforms to optimise transaction efficiency.