Voluntarily implemented carbon labels have shown that there is a lack of motivation by companies to develop technology to reduce carbon emissions. This study examined consumer values for mandatory carbon labels in South Korea. Considering the altruistic nature of carbon labels, we asked about individuals’ perceptions about the impact of climate change on their personal lives to measure consumer preference for carbon labels. Significant preference for mandatory carbon labels reflected Koreans’ high level of concern about climate change. As an increasing number of consumers feel the impact of climate change, the gap of WTPs between low carbon labels and carbon measured labels is sufficient. The lower value of low-carbon labels as compared to GM labels indicates that consumers’ guilt is not an appropriate strategy with carbon labels.