While many citizens have adopted digital channels for public service interaction, the use of traditional channels remains high, preventing economic benefits from digitalization. The channel choice (CC) and multi-channel management (MCM) fields of echoice of channels and the management of service interactions across channels. Research has mostly focused on either the citizen or organizational side and single channel communication. visits) is understudied. Therefore, we present a longitudinal quantitative study, which analyzes channel traffic data from two service areas, pensions, and parental leave, across three channels (letters, telephone calls, website visits). We apply interactivity theory and the concept of multiplexity to guide our analysis. We seek to offer contributions to the CC and MCM literature by demonstrating a relationship between outbound and inbound communication and the multiplex nature of government-citizen interaction.