Cities have a pivotal role to play in achieving net-zero emissions by 2050. Smart city solutions can help enable and accelerate the net-zero transition by, among many others, curtailing energy use, accelerating the shift from fossil fuels to renewable energy, improving resource efficiency, reducing transport demand, and fostering necessary behavioural change. This paper summarises the proceedings of the 3rd OECD Roundtable on Smart Cities and Inclusive Growth, which took place on 3 July 2023 at the OECD Headquarters in Paris. It discusses concrete solutions that can boost the net-zero transition, explores the barriers to scaling up smart city solutions and the enabling factors that can help overcome them, and proposes ways to strengthen the net-zero objective in the OECD Smart City Measurement Framework.