Exploring the relationships between physical accessibility, online behavior, and travel behaviour for grocery shopping in Scarborough, Canada

• Sufficient access is related to increased online grocery shopping frequency. • The influence of access on online grocery shopping is mediated by travel mode choices. • The relationship between online and travel behavior is intricate. • Proximity-based planning should anticipate changes in online behavior. The influence of proximity on travel behavior differs when online behavior is considered. While many studies treat online behavior as a moderator that weakens the benefits of local accessibility for sustainable travel, this moderation approach assumes that online behavior is independent of accessibility. Our study, in contrast, advances two alternative mediation models, i.e., the online mediation model and the travel mediation model, in which accessibility is explicitly linked to online behavior. Drawing upon a 2022 residential survey in Scarborough, Canada, these models are tested for grocery shopping, given its regularity, planning relevance, and limited existing evidence. Results support the travel mediation model: sufficient access to grocery stores within a 15-minute walk is associated with a lower likelihood of choosing a car as the most frequent travel mode for grocery trips and, consequently, with higher frequencies of online grocery shopping. This “physical accessibility–travel behavior–online behavior” pathway not only suggests that local accessibility may influence online grocery shopping, but also reveals a new mechanism by which spatial influence on online behavior occurs through changes in travel behavior. Findings also highlight the intricate relationship between travel behavior and online behavior. Specifically, online grocery shopping may not unidirectionally replace or modify in-store shopping trips; rather, it may be shaped by grocery trips. Lastly, the findings imply that accessibility planning should anticipate online behavior, because changes in travel behavior driven by accessibility may extend to online behavior, reflecting complex relationships between activities and travel in the digital era.