ABSTRACT Persuasive systems in different domains have been used to support people in changing their behaviours. These systems motivate desirable behaviour in users by providing relevant information, tracking user progress, and giving them feedback. This study investigates the persuasive features of a web-based information system that supports the enforcement of user commitments. A structural equation modelling approach and analysis of open text responses are used to identify the factors that affect the intention to continue to use the system, to gather users’ perspectives on how the system helps them to stick to their goals and the improvements that could be made. Data (N = 227) collected from the system's users is tested against the proposed research model. The results show that 30% of users’ continuance intention is explained by the implemented persuasive software feature categories (computer-human dialogue support, primary task support, perceived credibility, and social support) and perceived competence. Of these categories, primary task support has the strongest effect on perceived competence and continuance intention. The results also reveal how the system helps users to be consistent in their goals and the lack of specialised social support features. The study concludes with a discussion and recommendations for future research.