Employees rely heavily on computer-mediated communication (CMC). While CMC provides significant benefits, it also presents some challenges. The theoretical mechanisms underlying these opposing effects remain poorly understood, limiting our ability to mitigate the drawbacks of CMC use while maximizing its advantages. This study leverages job design theory to unravel the complex relationship between CMC use and employee basic need satisfaction, an important determinant of employee well-being and performance. More specifically, we propose that CMC use can satisfy the basic psychological needs of relatedness, competence, and autonomy as defined in self-determination theory, by providing social support, a critical job resource. However, it may also impede psychological need satisfaction by introducing technology-induced job demands, such as interruptions and techno-workload. A daily diary study among 143 employees reporting on at least 2 days of working from home corroborated these hypotheses: CMC use was positively related to daily relatedness satisfaction through enhanced social support. Conversely, it was negatively associated with daily autonomy satisfaction through task interruptions and techno-workload. We discuss the theoretical and practical implications of these results, confirming the dual role of CMC in fulfilling and challenging basic psychological need satisfaction.