The purpose of the article is to substantiate the impact of intensive development of marketplaces on the transformation of the trade sector in the region using the example of Rostov-on-Don. The relevance of the study lies in identifying the specifics of consumer behavior involved in the trading process through online and offline purchases against the background of numerous offers from sellers formed by technical and technological platforms represented by marketplaces. The features of consumption both online and offline are highlighted, in particular, the results of a survey of customers directly in retail chains in Rostov-on-Don are presented. The analysis of statis-tical materials for the Rostov region in terms of studying the characteristics of the online and of-fline trade sector, the main economic indicators for the top marketplaces of Rostov-on-Don, the forecast and trends of their development in this region and the impact on the gross regional product. Approaches to the integration of digital online trading resources into offline retail net-works are proposed in order to increase their customer orientation, personalize customer service and form digital literacy in the field of technical and technological trading tools for all subjects of the trading process.