<p>The construction sector in South America is a driver of economic growth, but faces increasing pressure to address resource scarcity and environmental challenges. In response, the circular economy (CE) concept has gained traction as a framework for sustainable transformation. This study investigates the adoption of the CE model among major construction companies operating in South America. A total of 65 sustainability reports from 13 companies were analyzed to identify CE practices and indicators implemented across the building life cycle stages: pre-design and design, manufacturing, construction, operation and use, and end of life. The analysis also tracks impacts over time. Results reveal that companies prioritize the end-of-life stage, followed by pre-design and design, operation and use, and construction; manufacturing is the least addressed stage. Practices include improving the quality of recovered materials, reusing in-situ concrete, advancing circular supply chains, and applying both building information modeling and pre-assembly, prefabrication, and modularization methodologies. Measurement, however, remains a key challenge. Circularity indicators are primarily reported during the pre-design and design, construction, and end-of-life stages. While impacts vary across companies, some reports demonstrate improvements in water efficiency, recycling rates, and waste reuse. Overall, findings suggest a growing adoption of circular practices; nonetheless, the integration of circularity indicators remains incipient and highly heterogeneous across companies. This research contributes to the understanding of circularity in South American construction and provides insights to advance practice.</p>