The rapid adoption of QR code payments using smartphones in Japan has led to significant changes in the country’s payment systems. This study aimed to clarify the mechanism behind the continued use of QR code payments services by focusing on consumer satisfaction and dissatisfaction. A hypothetical model based on the Expectation Confirmation Theory and Technology Acceptance Model was developed and tested using data collected through questionnaires from active users of QR code payments. Path analysis revealed that the fulfillment of expectations positively influenced perceived usefulness, satisfaction, and continuity intention while negatively affecting dissatisfaction. However, perceived usefulness did not significantly influence satisfaction or continuity intention, and, surprisingly, it positively affected dissatisfaction. The results suggest that users continue to use QR code payments not because they are satisfied with the service but because they are not dissatisfied with it, considering it as one of the various payment methods available in Japan. These findings provide valuable insights for QR code payment providers to develop their services. Further improvements in the model and questionnaire design are necessary to enhance the reliability of the collected data and the goodness of fit of the model.