Urbanization and climate change are intensifying global water scarcity, with the number of people facing water shortages expected to rise from 933 million in 2016 to 1.693–2.373 billion by 2050. India will be most affected, with its water-scarce urban population increasing by 153–422 million. Over 193 large cities are projected to face water scarcity by 2050, with 10–20 megacities affected. While two-thirds of water-scarce cities can alleviate scarcity through infrastructure, significant environmental trade-offs must be considered. Urban water scarcity is driven by population growth, urbanization, and climate change. Solutions include desalination, groundwater extraction, reservoirs, and virtual water trade. However, these solutions require substantial investment and may have environmental impacts. The study highlights the need for improved water-use efficiency, population control, and climate mitigation to address water scarcity. Despite the potential for solutions, 16 large cities, including two megacities, may not find viable options. The findings emphasize the urgency of sustainable water management to achieve the UN Sustainable Development Goals.Urbanization and climate change are intensifying global water scarcity, with the number of people facing water shortages expected to rise from 933 million in 2016 to 1.693–2.373 billion by 2050. India will be most affected, with its water-scarce urban population increasing by 153–422 million. Over 193 large cities are projected to face water scarcity by 2050, with 10–20 megacities affected. While two-thirds of water-scarce cities can alleviate scarcity through infrastructure, significant environmental trade-offs must be considered. Urban water scarcity is driven by population growth, urbanization, and climate change. Solutions include desalination, groundwater extraction, reservoirs, and virtual water trade. However, these solutions require substantial investment and may have environmental impacts. The study highlights the need for improved water-use efficiency, population control, and climate mitigation to address water scarcity. Despite the potential for solutions, 16 large cities, including two megacities, may not find viable options. The findings emphasize the urgency of sustainable water management to achieve the UN Sustainable Development Goals.