Purpose: The purpose of the study was to determine the moderating effect of economic growth on financial performance of merged institutions Methodology: The study adopted a mixed methodology research design. The study population included all the 51 merged financial service institutions in Kenya. Purposive sampling was used. Primary data was obtained from questionnaires and a secondary data collection template was also used. The researcher used quantitative techniques in analyzing the data. Descriptive analysis for the study included the use of means, frequencies and percentages. Inferential statistics such as correlation analysis was also used. Panel data analysis was also applied. Further, a pre and post merger analysis was used. Results: There was a significant relationship between the moderating effect of economic growth and financial performance of merged institutions. Unique contribution to theory, practice and policy: The government and Central Bank of Kenya to come up with strategies and policies to protect the financial services sector due to its immense contribution to the economy of the country by formulating policies aimed at controlling the effects of rapid fluctuations of the macro economic factors and their effects on the sector.