The growing prevalence of social networking sites (SNSs) has transformed the way that hospitality employees connect with their coworkers. Whereas it has been investigated that befriending coworkers on SNSs may transition to favorable workplace relationships, what conditions such friendship transitions is under-researched. Building on social penetration theory, this paper aims to explore employees’ virtual surface acting as a potential hindrance in cross-boundary relationship transitions, and how such a hindering effect could be attenuated by a supportive environment for boundary integration. A multilevel model is proposed to investigate how SNS friendship induces favorable workplace outcomes through reinforced workplace relationships. The moderating role of surface acting on SNSs and its interplay with supportive environment has been scrutinized. The results reveal that only suppressing negative emotions interferes with cross-boundary relationship transitions, while a supportive environment for boundary integration offsets this negative moderating effect. Managerial implications are provided for both employees and hotel operators.