Unless just and inclusive, transitions to low carbon-energy systems are unlikely to receive sufficient legitimacy and broad public support. While research on inequalities and injustices in energy transitions is growing, these issues remain less explored in the case of the digitalisation of the energy systems through smart grids and smart homes. This paper aims to synthetise our understandings of inequality, exclusion and vulnerability in energy transitions by systemically analysing different dimensions of marginalisation in the transition to a digitalised electricity infrastructure in Sweden. To synthetise understandings of marginalisation and exclusion, conceptualisations of these processes in different social science approaches to energy studies are reviewed. Moreover, an empirical analysis of interviews with a range of Swedish actors such as energy utilities, social housing developers or pensioner organisations is carried out and enriched by previous research on smart grid users. The empirical analysis demonstrates what specific forms that diverse categories of marginalisation, as already identified generally in different social science approaches to energy studies, may take in smart grids. We argue that marginalisation of household users in smart grids may take place along multiple dimensions, relating to matters of literacy, participation, infrastructure, and the economy. The analysis suggests that bundles of marginalisation aspects concerning household users in sustainable energy transitions should be recognised and addressed simultaneously.