The proliferation of E-commerce significantly transforms trade, connecting businesses and consumers in novel ways. In Kenya, Jumia, a leading online marketplace, exemplifies this transformation. However, the rapid growth of E-commerce platforms raises critical concerns about trust, security, and data privacy. Customers are wary of sharing personal details due to potential misuse and a lack of awareness about privacy settings, secure practices, and possible risks. Our paper investigates the effectiveness of trust-building mechanisms and data privacy through a qualitative approach, including a systematic literature review and case study analysis. Our findings highlight the importance of robust security measures, transparent policies, and user-friendly design in fostering consumer trust. In conclusion, while Jumia Kenya's practices align well with best practices, continuously enhancing data privacy measures is necessary to address evolving user concerns. We recommend increasing transparency in data handling, enhancing user education on privacy settings, and regularly updating security protocols. Our paper is relevant to managers, government bodies, academicians, and other stakeholders who shape e-commerce policies in Kenya, emphasizing the need for robust trust, security, and privacy measures to foster successful online business relationships.