Does smart city policy lead to sustainability of cities?

The popular smart city concept, for some, is viewed as a vision, manifesto or promise aiming to constitute the 21st century’s sustainable and ideal city form, while for others it is just a hype. This paper places smart city practices from the UK under the microscope to investigate their contributions in achieving sustainable urban outcomes. Panel data analysis methods were employed to investigate changes in carbon dioxide emissions level of 15 UK cities with differential level of city smartness over the period of 2005–2013. The findings reveal that the link between city smartness and carbon dioxide emissions is not linear, and the impact of city smartness on carbon dioxide emissions does not change over time. This finding calls for better aligning smart city strategies to lead to concrete sustainable outcomes. The paper concludes by highlighting the importance of prospective investigations to accurately scrutinise existing smart city projects’ outcomes, and emphasising the necessity of developing smart city agendas that deliver sustainable outcomes