The transition to a circular economy (CE) in the fashion industry is of high relevance for sustainability. This paper presents a methodological proposal for evaluating the maturity of CE adoption within manufacturing companies. With a focus on the Canton Ticino in Switzerland, where the fashion industry is highly specialized, this study examines the evolving landscape of the sector, highlighting shifts towards integrated logistics and outsourcing. A survey-based approach, complemented by targeted interviews, assesses the maturity of CE adoption among companies. Findings reveal varying levels of knowledge and adoption of CE principles, with significant opportunities for improvement identified. Key enabling factors include technological advancements, efficient reverse logistics, education, policy support, and consumer engagement. Challenges include the need for centralization in garment collection, enhanced sustainability education, and effective policy implementation. The proposed methodology offers insights into CE maturity levels, guiding stakeholders towards sustainable practices and fostering sector-wide circularity. Extension of this methodology to other sectors holds promise for comprehensive assessments and targeted actions, driving sustainable development on a broader scale.