Objective: This study examines how the depth of information in sustainability labels influences consumers' perceptions of product authenticity and reduces skepticism toward sustainability claims. Theoretical Framework: Drawing on consumer trust, authenticity in credence goods, and the role of detailed information in labeling, the study is grounded in sustainability labeling research and implicit attitudes, utilizing the Implicit Association Test (IAT) as a key measure. Method: A mixed-method approach combines surveys with the IAT to assess how label information depth affects perceived authenticity. Ninety-four participants from German-speaking Europe took part, with reaction times analyzed using Greenwald’s d-score method. Results and Discussion: Findings indicate a positive correlation between detailed label information and perceived authenticity, with a mean d-score of 0.73. Labels featuring quantified details foster greater trust, particularly among younger, educated consumers. The discussion underscores the role of transparency in mitigating skepticism. Research Implications: The study informs marketing strategies and policy by emphasizing the importance of clear, detailed labeling in building trust and promoting sustainable consumption. It contributes to Sustainable Development Goal (SDG) 12: Responsible Consumption and Production by providing insights into how transparent labeling can encourage ethical consumer behavior. Originality/Value: By focusing on implicit attitudes, this research offers insights into heuristic decision-making, showing that detailed sustainability information enhances perceived authenticity and trust.