Despite the growth of the circular economy in the last decade, consumer participation, particularly in circular business models, has still been little explored. Engaging consumers in the circular economy requires not only awareness but also a shift in behavior and mindset toward circularity. Based on the Meta‐Theoretic Model of Motivation and Personality (3 M Model), we explore the role of the big five personality traits as drivers of consumer engagement in a circular economy and their willingness to participate in the circular business model. To this end, we collected a sample of 489 Portuguese consumers, and the Partial Least Square method was applied to the formulated research model. The results demonstrate that personality traits directly affect consumer engagement with the circular economy but not willingness to participate in the circular business model. Engaging with the circular economy in advance is necessary for consumers' personality traits to influence their willingness to participate in the circular business model. Furthermore, this association is stronger if consumers are women and young people. This study contributes to the extension of the 3 M Model to circular consumer behavior and the multidimensionality of the concept of consumer engagement. Furthermore, the results demonstrate that consumers' greater willingness to participate in a circular business model depends on their personality and engagement with the circular economy, allowing companies and policy‐makers to adopt measures to promote the active role of the consumer in the circular economy.