In the perfect world, people do not have to wait to get anything. Business operations have the exact capacity available to serve every customer when the customer wants to be served, and no idle capacity. But in the real world, service providers have to match demand and capacity, especially when customers do not arrive at the service operations in perfect timing. In the restaurant setting, waiting time influenced customers’ repeat-purchase intentions. Previous studies examined how the purpose of dining impacts customers’ expectation of waiting time. Nevertheless, according to the authors’ knowledge, there are no studies evaluated how the composition of the dining members influence customers’ expectation of waiting time. The purpose of this study is to investigate how the composition of group members influences customers’ expectation of the waiting time