The agricultural sector is a major contributor to global biodiversity loss. Ecological focus areas (EFAs), such as extensively used meadows, hedges, and buffer strips, are a cornerstone in promoting biodiversity conservation. Previous research highlights social and personal norms as strong predictors of farmers' efforts to conserve biodiversity. Accordingly, we aim to segment Swiss farmers according to their social and personal norms and analyze how these segments differ in terms of pro-environmental behavior. Furthermore, we are interested in whether these segments differ in terms of farmer's self-efficacy, the importance of farm sales and biodiversity payments, farmers' political priorities, and socio-demographic and farm characteristics. For the empirical analyses, we used a unique dataset combining data from a survey of Swiss farmers (N = 882) with data on registered EFAs from the Swiss Agricultural Information System. We explored the segments based on responses to four items capturing social and personal norms toward biodiversity conservation using latent class analysis. To estimate the mean differences between segments, we used an analysis of variance and covariance. Our results showed that farmer segments with high social and personal norms implemented more EFAs than those with lower social and personal norms. Moreover, high social and personal norms were associated with enhanced self-efficacy, higher importance of biodiversity payments for farm income, stronger priority for environmental policies, and less intensive agricultural production practices. This study informs policymakers in designing social norm interventions that, for example, include information about society's approval of farmers' biodiversity conservation efforts.