As interactive marketing devices that serve as proximity-marketing tools, AI-powered voice assistants (VA) provide consumers with highly innovative convenience, which in turn fosters consumer–brand relationships (Wang, 2021). This research aims to explore the role of AI-powered VAs as a positive technology that offers consumers a sense of positive experiences, thus contributing to building a consumer-brand relationship. Based on the positive technology paradigm and transformation of flow strategy, this research conducted a 2 (locus of agency: high, machine-centric vs. low, human-centric) by 2 (brand image and voice congruency effect: incongruent vs. congruent) between-subjects experimental design. Then, ANOVA and structural equation modeling (SEM) analysis were conducted to explain how perceived control, flow, and happiness induced by the interaction with brands’ AI-powered VAs lead to the formation of brand loyalty under the moderating influences of brand image and VA’s voice congruency. A total of 316 participants were recruited via Prolific. The ANOVA analysis highlights the importance of user-centric agency, as people tend to desire to control their environment (White, 1959). Further, the results suggest that the congruency between brand image and VAs also leads people to positive reactions, as it improves their comfort and control (Rodero, Larrea, & Vázquez, 2013). SEM analysis results found that perceived control was a crucial factor that led participants to flow experience (Ghani et al., 1991). Further, this study found that perceived control could lead to a much broader aspect, such as an increase in happiness. Therefore, the overall study findings support the potential of AI-powered VAs as a positive technology. This research contributes to human-machine interaction, positive technology paradigm, and VA literature. In addition, this study provides beneficial insights for marketers and app developers.