The study assessed Union bank core values for customers’ service delivery in Edo State. The study was guided by three research questions and a null hypothesis tested. A sample of 100 respondents gave credence to the study using an accidental sampling technique. A descriptive survey was employed. The reliability of the instrument was 0.87 using Cronbach alpha formula. A structured questionnaire was the instrument to collect data. Mean and standard deviation was used to answer the research questions, while t-test for the hypothesis. From the result, it was discovered that the Union bank core values that influence customers’ service delivery are integrity, collaboration, and respect. The two groups of customers used for the study did not show any significant difference on customers’ service delivery in Union bank, hence the null hypothesis acceptance. Consequently, it was recommended that banks should provide a feedback mechanism that will allow customers to make constructive criticism of their operations for service delivery. Regulatory agencies in the banking sector should ensure banks adhere to their core values for customers’ satisfaction to improve turn over. Furthermore, Union banks should engage in periodic training for staff on their core values so as to engender proper application in customer dealings. Finally, recommendations were made for further studies such as determinants influencing effective customers’ service delivery by commercial banks.