The article examines the essence of the concept of financial stability of an insurer, conducts a financial analysis of insurance companies. The role of financial sustainability for insurers is determined, which is special because it determines the importance of ensuring a high level of financial stability and reliability of the insurer's activities. It is proved that the key factors in assessing the competitiveness of an insurance company are profitability, stability, financial strength and level of service. The factors influencing the financial stability of the insurer and the main criteria for ensuring the financial stability of the insurer are analyzed. It is found that an important criterion for ensuring the financial stability of an insurer is the availability of a balanced insurance portfolio, the formation of which is aimed at maximizing profit with minimal risk. The role of reinsurance in ensuring the financial stability of the insurer is substantiated. The investment activities of the insurer to accumulate significant financial resources are analyzed