Objective: ongoing changes in settlement patterns, leading to the expansion and consolidation of urban areas, together with the rapid development of digital technologies, impose a number of new requirements on the passenger transport system. Meeting these requirements necessitates coordinated operation and active interaction among all modes of public and private transport, as well as shared mobility services. In this context, a trend toward the formation of seamless transport systems within urban agglomerations can be observed. Therefore, the purpose of this study is to demonstrate that the integration of transport companies in the urban passenger transportation market will contribute to an increase in market performance. Methods: to achieve this objective, general scientific research methods were employed, including comparative analysis, generalization, induction, and deduction. In addition, methods of industry market analysis and statistical data analysis were applied. Results: the research has proposed a concept of a seamless transport system for an agglomeration. It developed options for cooperation among transport companies, along with a number of tools aimed at improving the performance of the market under study. An assessment of the performance of the passenger transportation market in St. Petersburg has been carried out. Recommendations for the development of the transport system have been substantiated, which will make it possible to improve not only the quality of transport services but also the efficiency of resources used by the passenger transport system in agglomerations. Practical significance: the results obtained may be used in the practice of state regulation of passenger transport and in managing the interaction of transport companies at the regional level, especially in agglomerations.