Research has shown that messages containing descriptive normative feedback can induce behavior change in the direction of the norm. However, the literature is mixed regarding the relative influence of more specific referent groups. This study compared the effectiveness of social normative feedback at increasing waste diversion, across four referent groups varying in their degree of specificity. A sample of 1,560 single-family households in California was randomly assigned to one of six possible conditions: specific normative feedback about their immediate neighbors, exemplary normative feedback about the best recyclers in their city, generic normative feedback about the other residents in their neighborhood, normative feedback about a statewide waste diversion target, information-only, or no-contact control. Households in the feedback conditions received a mailed personalized Home Waste and Recycling report comparing their diversion rate to an assigned referent group. Results showed that the normative feedback increased diversion rates compared to the control condition, but results did not show significant differences between the treatments. Additionally, negative reports were more impactful than positive reports. Findings are discussed within the framework of the Focus Theory of Normative Conduct, and the implications for large-scale applications.