The study sought to assess the relationship between derived claims ratio and financial performance of listed insurance companies in Nigerian, using six selected Nigerian Insurance companies as study cases. In the study, ex-post factor research design and data were collected from the companies` annual reports for the periods between 2011-2019, made available in the Nigerian Insurers Association Digest. Based on the analysis, the findings show that Net Claim, Net Premium, Expenses Ratio, and Risk-Based Capital have a significant effect on the financial performance of Insurance Companies in Nigeria. The study, therefore, concluded that the insurance companies should at all costs put in place strategies to ensure proper management of Net Claim, Net Premium, and Risk-Based Capital and entrust these in the hand of experts to yield the required results and also recommended, that the claim managers should work in cooperation with other sections of the insurer from the policy formation stage to its cessation. This will not only avert the payment of fraudulent claims but will promote the timely payment of genuine claims and increase the profitability of the firm through effective cost control.