Given the interconnectedness of climate change and sustainable development, policymakers and scholars have started to investigate how climate actions can contribute to achieving the Sustainable Development Goals (SDGs), and vice versa. To date, research has mainly focused on the national and international levels, while little is known about the interlinkages between climate actions and the SDGs at the transnational level. Not only nation states, but also non-state actors undertake ambitious actions designed to reduce greenhouse gas emissions and to promote sustainable development. Using content analysis and network analysis techniques, we examine the interlinkages between the climate actions of 72 transnational initiatives and the 169 targets of the 17 SDGs. We find that actions of 71 initiatives contribute to achieving 16 SDGs, thus generating valuable co-benefits. Besides SDG 13 on climate action and SDG 17 on partnerships for the goals, transnational climate actions frequently address SDGs 9 on industry, innovation and infrastructure, SDG 7 on affordable and clean energy, and SDG 12 on responsible consumption and production. While SDG 3 on good health and well-being and SDG 4 on quality education are barely addressed, SDG 5 on gender equality is not at all covered by transnational climate actions. Additionally, the network reveals that SDG 9 is highly synergistic with many other frequently addressed SDGs and functions as an important connector between them. Finally, our results indicate that transnational initiatives fill a governance gap left by states with regards to SDG 12. Climate initiatives of non-state actors can thus complement state-led actions to implement the Paris Agreement and the SDGs jointly.