The contribution to the 17 Sustainable Development Goals (SDGs) represents the next generation of measures for the sustainability of firms. We are the first to study the impact of a firm’s SDG performance on its value using unique data on SDG-aligned products and services from more than 5,800 global firms. Comparing firms that disclose their SDG performance to 25,800 non-disclosing firms reveals significant differences. We estimate an SDG disclosure-choice model and integrate the results into a firm-value model. Our results reveal the impact on firm value of specific SDGs; for example “combating hunger”, “attaining gender equality”, and “optimizing material use” have a significantly negative, whereas “ensuring health” and “mitigating climate change” have a significantly positive impact. The results remain robust after controlling for firms’ environmental, social und governance (ESG) scores and countries’ SDG performance. We recommend including a firm’s SDG performance to more precisely assess its value.