This study examined the effect of Information and Communication Technology (ICT) adoption on the financial performance of listed Deposit Money Banks (DMBs) in Nigeria, with specific focus on mobile banking, e-banking, and Automated Teller Machine (ATM) usage. The study adopted an ex-post facto research design, relying on secondary data extracted from audited annual reports of sampled banks, publications of the Nigerian Exchange Group (NGX), Central Bank of Nigeria (CBN) statistical bulletins, and Nigeria Inter-Bank Settlement System (NIBSS) reports. The population comprised all listed DMBs in Nigeria, out of which twelve banks were purposively selected based on data availability and continuous listing between 2015 and 2024, yielding a balanced panel of 120 bank-year observations. Panel data regression techniques were employed for analysis, following descriptive statistics, correlation analysis, and diagnostic tests including multicollinearity. The findings revealed that mobile banking has a positive and statistically significant effect on ROA, indicating that increased mobile banking adoption enhances banks’ profitability through improved efficiency, reduced transaction costs, and expanded customer reach. ATM usage also exhibits a positive and significant effect on financial performance, confirming its continued relevance in generating fee-based income and improving service accessibility. However, e-banking was found to have a negative but statistically insignificant effect on ROA, suggesting that its profitability benefits may be constrained by high operational, maintenance, and cybersecurity costs. The study concluded that mobile banking and ATM usage are critical drivers of profitability among Nigerian DMBs, whereas e-banking plays a supportive but less impactful role. The study recommended that banks strengthen mobile banking platforms, optimize the cost efficiency of e-banking systems, and strategically manage ATM networks to enhance financial performance.