Mergers and acquisitions (M&A) are increasingly popular transactions in financial markets, often seen as a faster and safer way to achieve growth and create value. However, research focusing exclusively on the insurance industry remains limited. This research article aims to synthesize the characteristics of existing studies, describe the methods and variables used, present the results regarding the impact on the value and performance of the companies involved, identify the main determinants of this impact, and finally, highlight the main gaps and directions for future research. Studies published up to 2025 were collected from the Web of Science and Scopus databases, resulting in a final sample of 28 articles. The analysis shows that the Journal of Banking & Finance, Journal of Risk and Insurance, and Journal of Risk Finance are the leading publication outlets, with J. David Cummins emerging as the most influential author. Publication peaks occurred in 2008 and 2011, although no sustained upward trend was observed. Most studies focus on non-life insurers and use U.S. data. Methodologically, event studies and DEA models dominate the literature, focusing respectively on shareholder value creation and firm efficiency. Findings remain mixed, since M&A transactions are theoretically expected to create value, yet empirical evidence shows considerable variation across contexts. Identified determinants of M&A performance include company size, prior M&A experience, geographic or sectoral diversification, payment method, ownership and business type, governance, and human resources.