In the context of moving to a low-carbon economy there is wide interest among policymakers to improve knowledge of decisions surrounding residential heating systems. This research examines four aspects of decision-making with respect to heating system upgrades: home-owner decisions on whether to upgrade, decisions on fuel choice, fuel switching patterns, and an examination of the reasons why home-owners make these decisions. Among the key findings are that proximity to energy infrastructure, e.g. gas network, is an important determinant of residential heating systems upgrades, including fuel choice. With one exception no clear trend emerges on the likelihood of a broad range of socio-demographic variables, including age, income, and working status on home-owner decisions. A cohort of home-owners defined across a few socio-demographic characteristics, including mortgage holders, are predisposed to investing in a heating system upgrade compared to their peers but for reasons unknown do not invest. We also find that environmental concerns, across a number of dimensions, are not an important determining factor in either the decision to upgrade or the subsequent choice of heating system. Information on heating system alternatives is critical for good decision-making but we find that home-owners do not always rely on independent energy consultants for guidance.