Recently, the academic community has acknowledged the theoretical potential for promoting circularity in the construction industry through the integration of blockchain technology and Material Passports (MPs). Yet, this potential remains mostly untapped in practice, contributing to a significant gap between theoretical frameworks and practical applications. This study therefore intends to explore the potential of blockchain-based Material Passports (BBMPs) by identifying their inherent opportunities and the barriers impeding their adoption into AEC-practice. Based on a comprehensive literature and practice review exploring the underlying concepts of Material Passports and blockchain technology, the research design features a multi-method approach with inductive and deductive logic of inquiry. Method one, semi-structured interviews, explore the first two research questions, followed by method two, a comparative case-study analysis of two early attempts at BBMPs, answering the last two research questions. The PESTLE framework of analysis served as the primary method of analysis to identify and categorize relevant BBMP-adoption barriers. The examined cases revealed a list of opportunities of BBMP-adoption in form of relevant use cases, as well as a final list of barriers for their adoption into industry practice. Aimed at a wide audience, this research contributes to academia and practice by synthesising previously studied aspects, studying early attempts at BBMPs in practice, and highlighting areas for future research by identifying opportunities and barriers of the adoption of BBMPs in AEC industry practice.