Purpose: In the field of trade and freemium services, this study adds to the body of research on switching intentions by examining the direct and moderating effects of willingness-to-pay and push-pull motivations on conversion intention. These effects differ from the mooring effect in the original push-pull-mooring (PPM) framework. Research design, data and methodology: A systematic literature study was conducted using VOSviewer as a bibliometric tool to cluster keywords and determine the extent of research on switching behavior in freemium services. To test the predicted relationships, this study used partial least squares structural equation modeling (Haenlein & Kaplan, 2004) and the latest SmartPLS software. A non-probability quota sampling approach was used to select 619 respondents who were highly representative. The sample quota was determined by considering the proportional distribution of age groups and genders among Vietnamese Internet users. Results: The research found that the option to trial the premium version had a greater impact on conversion intention than perceived advertising intrusiveness in the free version. Conclusions: The analysis showed that an effective advertising plan can outperform a limited-use strategy to push the free version. In pull motivation, clients' desire to pay moderates their conversion intentions more than in push motivation does in the trade context.