Referential explanation (e.g., comparison with other customers) is often used to reduce the negative effect of service failures such as service delays. Existing studies focus on downward comparison with the belief that a consumer will feel less unhappy if s/he is compared to other consumers who have worse experience than him/her. This research argues that during service delays, customers often are uncertain about how long the service delay will last. Given the uncertainty, upward comparison may be an effective strategy if the consumers assimilate with the upward referent group and thus believe that their final outcome will be as good as the comparison target. Focusing on two major elements of social comparison, namely comparison direction (i.e., upward comparison vs. downward comparison) and comparison target (i.e., similar others vs. dissimilar others), we propose that assimilation/contrast mode that the consumers engage in may affect the way they interpret social comparison information and hence their satisfaction and revisit intention. Existing research on assimilation and contrast (e.g., Horen & Pieters, 2012; Ruys et al., 2006) suggests that whether the consumer will assimilate with or contrast from the comparison target depends on whether they consider the comparison target as a valid comparison benchmark. We expect comparison with other similar consumers may signal the presence of comparison standard and lead to contrast. Comparison with dissimilar others signals the absence of a comparison standard and thus results in assimilation. As a result, downward (upward) comparison may be more effective when making social comparison to similar (dissimilar) others.