The article considers topical issues of how banks are developing in the new realities of the digital economy, and presents the results of research on theoretical and practical aspects of banks' business models evolution. The methodology uses such approaches as scientific abstraction, system and factor analysis, methods of grouping, detailing, and synthesis. The topic is relevant for banks first of all from the economic science point of view, since until now the conceptual apparatus of not only the types of bank business models but also the definition of bank business models and their ecosystems remain controversial. However, in practice the applying of new strategic solutions is needed to solve the triune task: to ensure profitability of banks' business while maintaining liquidity and minimizing risks. The obtained results allowed us to reveal the important role of the banks' business models innovative transformation, as well as to reveal the tendency of improving the intermediary function of banks on the modern stage of digital technologies' development. The article substantiates the need to develop new approaches to administering business processes, expanding banking activities using digital platforms, and reveals the problem that requires the speediest solutions in developing regulation standards for financial ecosystems.