Efforts to tackle climate change are taking place on multiple fronts. This includes trade, an increasingly important defining feature of the global economy. In recent years, free trade agreements (FTAs) have become the primary mechanism of trade policy and diplomacy. This study examines the development of climate action measures in FTAs and discusses what difference they can make to tackling climate change. Its primary source research is based on an in-depth examination of FTAs in force up to 2020. This paper is structured around a number of research questions forming around three main inter-related areas of enquiry. Firstly, to what extent are these provisions in FTAs essentially derivative of energy’s connections with climate change, and thus part of a wider trade−climate−energy nexus? Secondly, what kinds of climate action are FTAs specifically promoting, and how effective a potential positive impact may we expect these to have? Thirdly, are certain climate action norms being promoted by trade partners in FTAs and if so, then who are the norm leaders, what is motivating them, and to what extent are they extending their influence over other trade partners? In addressing these questions, this study offers new insights and analysis regarding a potentially important emerging trend in the trade−climate−energy nexus. Its international political economy approach and latest empirical research also provide a further distinctive contribution to knowledge in this inter-disciplinary area, developing new comprehensions of the relationship between trade, climate action and energy.