The smartphone can be used for two context-incongruent purposes (work-related use at home and private use at work). In order to better understand these two behaviors concep- tually, we aimed to (1) identify subgroups of context-incongruent smartphone users and (2) identify differences in demographic, smartphone-related, and occupational health-related characteristics among the identified subgroups. We conducted an exploratory and data- driven latent class analysis of work-related smartphone use at home and private smartphone use at work (self-reported) in a large cross-sectional sample of Dutch fulltime employees (n=1544). Our analysis revealed that most employees engage in context-incongruent smartphone use and identified four smartphone user classes. Comparisons of frequent and infrequent context-incongruent smartphone users revealed several interesting insights regarding demographic (e.g., frequent users were younger, more likely to be married or in a relationship, and less likely to work from their employer’s site), smartphone-related (e.g., frequent users were more likely to be provided a smartphone by their employer, attached more importance to their work-related and private smartphone interactions, and reported higher fear of missing out), and occupational health-related (e.g., frequent users reported only slightly higher job demands, job control, and work-home interference, but at the same time lower segmentation preferences and psychological detachment) characteristics. These findings provide insight into the wide-spread occurrence of context-incongruent smartphone use and could help to develop theory on and understand the outcomes of these modern behaviors. They could also help organizations to better understand their em- ployees’ behavior, which is a crucial first step in policy development.