The remarkable advances of mobile technologies and the prevalence of mobile devices have profoundly transformed telephony systems. They provide functionalities which surpass telephony needs, and which motivate the development of value-added mobile services and functions. The literature highlights the fact that mobile transactions (m-transactions) are one of the most critical incentives for successful mobile commerce (m-commerce). However, the successfulness of m-transaction systems in Saudi Arabia requires a strong acceptance of consumers. The importance of this study is accentuated by the fact that mobile commerce and its services are still in their infancy and there is still an apparent lack of acceptance of mobile transactions amongst Saudi users. This study will investigate the acceptance of using m-transaction by applying Technology Acceptance Model (TAM) which one of the well-established models in addressing technology acceptance by surveying more than 1000 Saudi users. Key Words: Mobile Technologies; M-Transactions; TAM; Acceptance; Developing Countries.