PurposeReferral reward programs (RRPs) incentivize existing customers (inductors) to refer new customers (inductees). The effectiveness of RRPs is not well understood as previous studies either focused on referral intent and/or ignored inductee responses. However, an RRP is only effective if inductors recommend and inductees respond with buying the service. The purpose of this paper is to examine the drivers of existing customers’ successful referral behavior.Design/methodology/approachThis study combines a bank’s customer relationship management (CRM) data which were used to identify successful inductors and non-inductors. Then, observed behavioral and customer background data from the CRM database (including successful referrals, deposits in euros, number of products held, relationship duration, income, age, and gender) were combined with survey data capturing attitudinal variables (i.e. perceived relationship quality, reward attractiveness, referral metaperception, opportunism, and involvement). This approach allowed for the simultaneous testing of all hypothesized drivers of successful referral behavior.FindingsMetaperception (i.e. the process by which individuals determine the impressions other might form of them and their behavior) was the strongest and most significant driver of successful RRP participation, followed by attractiveness of the reward. That is, inductors recommended successfully when they believed that their incentivized referral did not look bad (or even looked good) and incentives were perceived as attractive. This finding is important as metaperception so far has only been examined in theoretical and experimental studies with intent as dependent variables. Second, latent class analysis (LCA) revealed that there were two segments of inductors of which one was opportunistic. Opportunism as a driver of referral behavior has not been shown in past research using more traditional analyses, whereas LCA uncovered it as a driver for one-third of all respondents.Practical implicationsThe findings offer managers a better understanding of the key determinants of successful referral behavior with important RRP design implications that counter frequent practice (e.g. designing RRPs with high face value but then reducing its usefulness through terms and conditions). Furthermore, managers may consider segment-specific reward structures to improve the effectiveness of their RRPs.Originality/valueThis study is the first to examine inductor determinants of successful referral behavior and identify inductor segments.