This study examines the Sustainable Urban Mobility Plan (SUMP), which was developed for the Trabzon Metropolitan Municipality in line with the European Union’s vision for sustainable mobility. The project aims to improve the quality of life in Trabzon by developing its transport infrastructure in line with sustainability principles. The planning process was carried out using a stakeholder-based, data-driven and holistic approach. Comprehensive field studies, household surveys and preference surveys conducted in Trabzon revealed the city’s mobility profile. Analyses using an activity-based transport model showed that most daily journeys are made by private vehicle, while public transport and active travel modes are underused. Projections based on the current situation indicate that traffic congestion and environmental problems will worsen when the population and car ownership are expected to increase in 2040. In this context, SUMP proposes measures to reduce dependency on private vehicles, develop public transport and promote active travel. The study also emphasises the importance of developing institutional capacity and fostering collaboration among stakeholders to ensure the plan is implemented effectively, thereby contributing to Trabzon’s long-term development as a sustainable and liveable city.