Objectives: Belgium enacted a coronavirus disease 2019 (COVID-19) pass – the ‘COVID Safe Ticket’ (CST) – in October 2021. This study aimed to understand the expectations and reasons given by those supporting this policy measure. Methods: This mixed methods study was based on a voluntary online survey among 9444 French-speaking residents in Belgium. Results: Most respondents were not very supportive of the CST, with only 617 respondents (7%) being pro-CST. Compared with other respondents, the pro-CST sample comprised more males, older people, people scared of COVID-19, people who had confidence in the COVID-19 vaccines, and highly educated people. A qualitative analysis was undertaken to identify the reasons why respondents supported the CST. Two lines of argument were related to personal comfort (individual protection and means of ‘recovering freedom’), and two other lines were related to collective protection (controlling the pandemic and incentivizing vaccination). Pro-CST respondents also indicated some limitations of the CST. Conclusions: The expectations regarding the CST were high, diverse and not entirely rational. Some contradictions and frustration emerged from the respondents’ comments. The CST may have exacerbated the social divide in society. The high expectations risk leading to comparably high levels of disappointment, resulting in potential distrust towards future public health interventions.