This article delves into local public diplomacy from the perspective of climate action. A cross-sectional analysis is made of the climate perspective in the international 2030 Sustainable Development Agenda, considering the social, political, and economic challenges implied by human alteration of the environment. The websites of local municipal corporations in Portugal are analysed to identify the information referring to Agenda 2030 and its convergence in climate action. To this end, a content analysis method was designed based on the relationship of the Agenda’s sustainable development goals (SDGs) with their associated climate change goals. Attention is paid primarily to the websites’ fixed sections, and secondarily to their informational content and external portals. The method is applied to the websites of seven of Portugal’s municipalities. Conclusions are drawn concerning whether or not they provide information on climate change so that the effort directed by these local governments towards climate action can be determined. A comparison is made with the international case. This tool contributes to localizing the SDGs and prioritizing environmentally important components.