According to the United Nations (UN), although cities occupy only 3% of Earth’s surface, they host more than half of the global population, are responsible for 70% of energy consumption, and 75% of carbon emissions. All this is a consequence of the massive urbanization verified since the 1950s and which is expected to continue in the coming decades. A crucial issue will therefore concern the management of existing cities and the planning of future ones, and this was also emphasized by the UN Sustainable Development Goals (SDGs), especially in Goal 11 (Sustainable Cities and communities). Smart Cities are often seen as ideal urban environments in which the different dimensions of a city (economy, education, energy, environment, etc.) are managed successfully and proactively. So, one of the most important challenges cities will have to face, is to guide citizens towards a form of “clean” energy consumption, and the dimension on which decision-makers will be able to work is the decarbonization of transport. To achieve this, electric mobility could help reduce polluting emissions on the road. Within this research, the strategies that six Smart Cities (London, Hamburg, Oslo, Milan, Florence, and Bologna) have implemented to encourage the transition to this form of mobility have been studied. Through a systematic review of the literature (Scopus, Google Scholar, and Web of Science) and through the study of the main political/energy documents of the cities, their policies on electric mobility have been evaluated. Then, for each city, SDG 11.6.2 was analyzed to assess the air quality in the last four years (2016−2019) and, therefore, the effectiveness of the policies. The analysis showed, in general, that the policies have worked, inducing reductions in the pollutants of PM2.5, PM10, NO2. In particular, the cities showed the most significant reduction in pollutant (above 20%) were Hamburg (−28% PM2.5 and −2%6 NO2), Milan (−25% PM2.5 and −52% NO2), and London (−26% NO2).