A common finding in behavioural economics is that people often procrastinate, i.e., keep postponing planned tasks or decisions that require effort to execute. The effect of procrastination on inter-temporal energy choice behaviours could be even more serious because energy is an abstract, invisible and intangible commodity. This paper uses a web survey to investigate how people's procrastination propensity and environmental awareness affect their heating-energy-saving behaviours. The results indicate that people who state that they have a higher tendency to procrastinate are significantly less likely to have engaged in most of the heating energy-saving activities, especially regarding larger purchases or investments in equipment and the insulation of doors and windows. I also found a positive relationship between environmental awareness and engaging in everyday energy-saving activities such as reducing the indoor temperature. The findings suggest that measures aimed at reducing procrastination are needed to realise energy-saving potential. It is important to find ways to either bring future benefits closer to the present or to magnify the costs of delayed action. For example, one can employ certain feedback systems and commitment devices to make current gains and future costs more visible or tangible. (C) 2013 Elsevier Ltd. All rights reserved.