The article suggests methodological approaches to assessing financial stability of the banking system of Ukraine based on the use of comprehensive and taxonomic indicators with FSI taken into consideration. The paper outlined comparative methodology allowed to test the procedure of assessing financial stability to compare the practical effectiveness of the two methods. The proposed valuation methods, owing to their clarity, data availability and, ease of implementation, were convenient and could be used by regulators, individual banks, and consumers of banking services. It was emphasized that the issue of assessing the financial stability of the banking system was especially relevant in the context of new realities that constantly pose new challenges. Additionally, it was noted that the specific banking system has been particularly vulnerable to external factors, the influence and force of which it cannot control. As a result, the importance of the timely selection of an appropriate method for assessing the financial stability of the banking system makes it possible to identify weaknesses and trends in its dynamics to maximize the smoothing of the above factors. According to the comparative study was concluded that the taxonomic indicator method was more practical than the complex index, as it eliminated the risk of subjective contribution in the methodology of index development at the stage of providing weights for indicators. Also, the outlined method is authorized to apply the forecast component in the analysis and predict which direction financial stability will develop. The conducted research allowed to identify trends in the development of financial stability of the banking system of Ukraine. The development of rapid practical methods for assessing financial stability of the banking system was shown to be promising in highlighting main trends in the dynamics of its state to quickly respond to the challenges of new realities.