This study examines the relationship between financial intermediation activities and net interest revenue among publicly listed commercial banks in Nigeria. This study enhances the existing literature by investigating the direct effects of core intermediation indicators, such as deposit mobilization, credit allocation, financial intermediation costs, loan-to-deposit ratio, and branch network size, in contrast to previous research that primarily focused on interest rates and overall profitability. A quasi-experimental research approach was employed, utilizing secondary data obtained from the annual reports and financial statements of publicly traded commercial banks, in addition to the Central Bank of Nigeria’s Statistical Bulletin. We used the Statistical Package for Social Sciences (SPSS) to look at the data. Net interest income was the dependent variable, and the intermediation variables that were found were the independent predictors. The empirical findings indicated that financial intermediation variables collectively accounted for 52.5% of the variation in net interest income. Deposit mobilization and credit allocation had a positive and statistically significant effect on net interest income. On the other hand, financial intermediation costs, the loan-to-deposit ratio, and branch expansion had negative and statistically insignificant effects. Based on these results, the study suggests that commercial banks use cost-effective intermediation methods to boost investor confidence. It also says that the Central Bank of Nigeria should lower the amount of cash it needs to keep on hand to make it easier for businesses to get loans. It is also a good idea to strengthen attempts to get more deposits in order to better manage liquidity, increase lending capacity, and make more money. Also, to keep the bank’s performance up, it’s important to optimize the loan-to-deposit ratio and use good cost management procedures. From a policy point of view, the Central Bank’s Monetary Policy Committee needs to make monetary policies that encourage more deposits to be moved about in the banking system.