The principal aim of the paper is to determine the impact of reinsurance operations in commercial insurance companies, in accordance with the relevant accounting legislation, for certain significant items of the financial statements. In actual fact, the reinsurance operations affect the profit of a commercial insurance company, following the financial statements. The prerequisite for fulfilling the objective of the paper is to analyse the accounting legislation for reinsurance operations in commercial insurance companies. Attention will be devoted also to the method of accounting for reinsurance operations and their specific reporting in various parts of the financial statements of commercial insurance companies. The partial aim of this paper is to identify significant differences in the area of accounting of commercial insurance companies, based on the comparison of accounting practices of the issues examined in accordance with IAS/IFRS. In the conclusion, the authors will address the latest development of necessary steps in adopting the concept of IFRS 4 Phase II and accomplishing the process of the application of IFRS 4 Phase II to the accounts of commercial insurance companies.