The importance of household behavior in energy consumption is regularly raised in literature. Nevertheless energy-economy long-term planning models still often represent energy demand by a single mean household and thus fail to capture household behavior. This paper describes the original modeling approach developed within the TIMES model framework in order to take household behavior and heterogeneity into account: the TIMES-Households model. This model depicts both household daily energy consumption and equipment purchasing behavior and focuses on the French residential and transport sectors. We show the importance of taking household heterogeneity into account in long-term planning models within the comparison of two energy price scenarios applied to two different models. Finally, thanks to the highly disaggregated representation of households and their behavior in the model, we address the problem of unrealistic technology diffusion pathways often obtained when using an optimization bottom-up model. (C) 2014 Elsevier Ltd. All rights reserved.