The Internet of Things (IoT) represents a shift towards a digitally enriched environment connecting smart objects and users that promises to provide retailers with innovative ways to approach their customers. IoT technologies differ from previous innovations as they are ubiquitous, intelligent and autonomous. Research into the customer acceptance of IoT services in retailing is scarce and the relevance of technological autonomy has been neglected. Hence, the aim of this research was to assess the relevance of technological autonomy in the IoT service acceptance and to investigate factors influencing the willingness to accept. Based on the technology acceptance model (TAM) this research proposed a new model that consists of seven perceptional factors and degree of autonomy. In a between-subject experimental design, data from 167 supermarket customers was analysed using multiple (moderated) regression. First, degree of autonomy statistically significantly influences intention to accept IoT retail services. The results emphasize that the customer acceptance intention of IoT services decreases when technological autonomy grows. Further, support for the positive direct effects of perceived usefulness, compatibility, enjoyment, and technology trust in intention to accept was found. Ease of use, behavioural control and credibility did not play a significant role. Remarkably, support was found that enjoyment and technology trust gained relevance in situations when technological autonomy was high. These findings highlight that perceptions of relative advantage in enjoyment and trust are important, especially when technologies are highly autonomous. Finally, the insignificance of ease of use challenges the robustness and applicability of TAM in latest technologies. The findings encourage future research to consider degree of autonomy in other contexts of IoT technology acceptance.