Abstract Commitment to increase public awareness of climate change mitigation has risen substantially and so has the appreciation of the impact that comes from voluntary behaviour change. We aimed to test whether a process could be designed that encouraged individuals – from within their existing social networks – to facilitate energy reduction discussions that ultimately changed the way they consumed energy. Our “Energymark” process was grounded in the idea that change is facilitated by several supporting factors including the provision of tailored information, social support, encouragement to set goals, and access to feedback. In this paper we report on the first trial with members of the Australian public. By the end of the trial an average emissions reduction of 20% was reported using a pre- and post-trial carbon calculator incorporating the energy used at home, waste, spending on products and services, beef consumption, and transport. While many identified as climate change aware, and had the socio-economic capacity to make changes, we found that participants of widely varying demographics and dispositions responded to program features, achieving equivalent emissions reductions. This bodes well for the program’s effectiveness and warrants further testing of the impact of voluntary action with social processes such as Energymark.