Currently, there is an ongoing debate related to the large environmental impact of livestock greenhouse gas (GHG) emissions and the negative effect of saturated fat contained in the animal foods on human health. In response to these adverse effects, dairy producers have adopted strategies to reduce these effects by modifying the conventional livestock feed composition. This study investigated, for the first time, Finnish consumers’ willingness to pay (WTP) and heterogeneous preferences for butter derived from milk produced by cows fed with lipid-rich rapeseed feed, hereafter called rapeseed feed, which can reduce the GHG emissions from cows, and the saturated fat content of dairy products. Using a hypothetical choice experiment (CE) involving butter that varied across four attributes (i.e. type of feed, saturated fat content, Carbon Trust label, and price), our results show that, on average, consumers preferred the low-price butter, produced from cows fed with regular feed, labelled with the claim “Reduced saturated fat”, and branded with the “Carbon Trust” label. Interestingly, we found that one-third of consumers were willing to pay a premium price for butter derived from milk produced by cows fed with rapeseed feed. Furthermore, we found that younger, and higher educated consumers tend to prefer butter derived from cows fed with rapeseed feed. These findings provide useful insights into the psychology of consumers’ level of acceptance and attitudes that can be used by dairy producers and marketers in communicating to the public the nature of the new feed practices to reduce the negative environmental emissions, and saturated fat content of dairy products.