Growing world trade puts forward the importance of trade liberalization and facilitation issues. As trade liberalization efforts of both governments and international organizations have mostly been successful, the importance of bureaucratic and informal impediments to international trade has been increased. An important part of these impediments is generally composed of complicated customs procedures and documentation requirements that generate the principal part of customs-related transaction costs. In this study, we examine the role of several factors in the determination of customsrelated transaction costs, especially the waiting time to clear the cargo already in some Turkish ports. We evaluate the following determinants of customs-related transaction costs such as complexity of customs procedures, customs personnel, obtaining certificates of conformity/approval or laboratory analysis, firm size, implementation and integration of computerized systems, and country of origin. We find that these six factors exert their effects on customs-related transaction costs either through affecting customs risk analysis or through affecting the clearance time (even in the same line).