Cities worldwide face immense challenges in transitioning to a sustainable future. While being structurally and politically bound to continuous growth, the striving for a constant increase in production and consumption puts enormous pressure on our planet and its ecosystems. Degrowth has been proposed as a pathway to solving this dilemma. Although scholarly attention to urban degrowth has expanded, a central aspect of cities remains partly unexplored: mobility. Urban mobility, being motorized and dependent on fossil fuels, has a substantial environmental and social impact, making it a central issue for sustainability. Within mobility research, urban sustainability has primarily been addressed by problematizing automobility and discussing how to replace the car as the dominant mode of transport. However, the relationship between mobility and growth extends beyond cars and needs to be addressed more generally. This article develops and expands the conversation between the degrowth and sustainable mobility literatures through a theoretical exploration of the concept of “limits.” It proposes a relational conceptualization of limits, providing an analysis of this concept in relation to key vectors of urban mobility: space, speed, and the body. Our study suggests not only that limits should be conceptualized along these vectors but also that these specific limits could be used to tease out what sustainable urban mobility might mean in practice.