<p>Cities have taken the lead in setting targets to reduce household and energy-related greenhouse gas emissions, yet the challenge of reducing emissions from the growing construction sector remains largely unaddressed. Globally, cities still lack information on current construction-related emissions and the reductions needed to stay within climate limits. Here we estimate construction consumption emissions and carbon budgets for over 1,000 cities worldwide. We show that construction emissions are converging around 1–3 metric tons of CO₂ equivalents (tCO₂e) per capita per year—a level that could use up most or all emissions allowed by a 2 °C climate target in 2030. To stay within this target, cities must reduce their construction emissions below 10% of current levels no later than the next 2–4 decades, necessitating substantial changes and a rethinking of construction practices. Our findings, showcased through an open dashboard, can help city-level stakeholders create science-backed plans for meeting future construction demand within climate targets.</p>