PurposeThis study investigates impulse buying as a consumer behaviour outcome in omnichannel retail through the stimulus-organism-response (S-O-R) theory. For such, the authors addressed convenience and channel integration as the stimuli, the relationship among consumer empowerment, trust, satisfaction, and perceived value as the organism, and impulse buying as the response.Design/methodology/approachAn online survey was conducted with 229 customers of a Brazilian retailer that adopts the omnichannel strategy. Data were analysed by partial least squares structural equation modelling (PLS-SEM).FindingsChannel integration and convenience had a positive influence on consumer empowerment which, in turn, influenced customer satisfaction and trust, producing direct and indirect effects on their perception of value relative to the retailer. In addition, impulsive buying was significantly influenced by perceived value.Practical implicationsThe results indicate that retailers that use the omnichannel strategy need to be alert to the factors mentioned above. The study empirically demonstrates that investing in channel integration increases customer empowerment, which will significantly improve customer trust and satisfaction and, eventually, customer impulse buying from the retailer.Originality/valueThis work contributes to the literature on marketing and consumer behaviour by identifying factors that influence consumers' impulse buying behaviour in the context of omnichannel retail. It suggests that impulse buying may be a relevant variable to understand the reaction of consumers empowered by the integration of the marketing channels and the convenience offered to them in an omnichannel retail environment.