Abstract Background: The present study aims to reveal the important role of subjective knowledge and perceived reliability for information in transforming purchasing intentions into a practical purchase in the consumer marketing literature and suggests that improving consumer knowledge and trust in corporate claims (based on On ethics), with the disclosure and public dissemination of quality information such as the participation of retailers and manufacturers in fair trade and related activities, especially in strengthening the sale of fair trade products. Method: The present study is applied and descriptive-correlational. The statistical population included buyers of convenience store stores in Urmia metropolis, from which 385 people were randomly selected. The research tool was a researcher-made questionnaire. Finally, the data were analyzed using structural equation modeling (Minimum Squares (PLS)) in SPSS software version 24 and SMARTPLS. Results: The results show that without strengthening the basic knowledge of consumers or improving their literacy, lack of knowledge probably prevents the growth of ethical consumption, so one of the most important factors to strengthen fair consumption is not the amount of information but especially the content and quality of information. Companies must enable consumers to obtain sufficiently reliable information to compare products based on ethical considerations (ie, fair trade). Conclusion: Subjective knowledge modulates the positive relationship between purchasing intentions and ethical purchasing behavior, but the moderating role of perceived reliability for information was not significant.