For many years, the public sector has been undergoing digital transformation. Information and communication technologies (ICT) have offered new ways of interaction between governments and their constituents. However, governments face different challenges to migrate users towards digital channels and electronic documents, which are believed to be more cost-efficient for all stakeholders. Despite a plethora of empirical research conducted towards the identification of factors that influence e-government services usage by businesses, there seems to be a lack of 'holistic' understanding in the absence of systematic literature reviews. This paper aims to contribute by hypothesizing a set of mechanisms based on a critical realist process of retroduction. We argue that the factors identified in previous research are a manifestation of mechanisms. Such mechanisms might explain businesses’ usage of ICT when interacting with governments, whether in the context of incidental situations or regular administrative tasks (through online self-service applications) or regular exchange of information (through inter-organizational e-services).