It is increasingly more interesting to the bank managers to understand what is important to customers when it comes to Internet banking, and especially banking conducted by the customers themselves. Corporate customers and Internet banking have been studied very modestly in the past, especially the decision-making factors that drive customers to go online. The purpose of this research is to identify the factors that influence corporate customer's adoption of Internet banking services in Kenya, Uganda, Tanzania and Rwanda. The hypotheses are empirically evaluated by the use of Trade Finance customers of an East African bank that serves as a target sample. The Technology Acceptance Model (TAM) is the primary basis for the study. The information gathered from former studies that are mainly concentrating on private customers, acts as a foundation for the development of an extension of TAM that is suitable for corporate customers. The study involves 137 respondents from Kenya, Uganda, Tanzania and Rwanda. Due to the quantitative nature of the study, the results are analysed with statistical measures which include the use of SPSS in order to carry out regression analysis.