The present study explores how smart cities communicate their actions and performance against climate change to their stakeholders –most importantly citizens- through their annual reports, in a period where public sector standard-setting boards' interest on the topic is escalating. It answers the call for more technical results rather than theoretical discussions on the development of climate change reporting in the public sector. Smart cities are environmentally friendly and citizen-centered, thus closely related to constituents' quality of living, but their infrastructure/technological emphasis could trigger climate change phenomena. The annual report is the basic accountability means to stakeholders, and a communication tool for impression management purposes. Results show different approaches adopted by smart cities located in different parts of the world, with the use of qualitative performance measures exceeding that of quantitative measures. The results show trends and approaches that can be useful as a basis to reflect upon, during the development of relevant reporting guidelines by standard setting boards.