Trust constitutes, on the one hand, a central social resource for the emergence and development of social belonging within organizations. On the other hand, social trust relationships enable the drawing of social boundaries of belonging within and towards organizations. This contribution examines the extent to which trust generates social boundaries of belonging in organizations. It is assumed that ongoing reciprocity or social exchange between organizational actor groups can create trust spaces within organizations, which may exhibit different qualities. Organizational trust spaces can thus take on a more inclusive quality or, conversely, a reductive and exclusionary character. Using the example of a residential elderly care facility, the analysis explores which internal social constellations contributed to the social genesis of reductive trust spaces. The findings indicate that, in particular, leadership groups as third-party actors play a significant role in the development of reductive and socially exclusive trust spaces in organizations. Furthermore, symbolic boundary drawing proved to be the basis for the emergence of manifest social boundaries, which resulted in certain employee groups being excluded from participation in generalized social exchange relationships. Following the case study results, further research perspectives are outlined and implications for an inclusive, trust-based leadership practice are discussed, such as the social equidistance of leaders towards different employee groups. From a theoretical and conceptual perspective, this contribution connects figurational and organizational sociological approaches.