The literature on immigrant transnationalism and on irregular immigration suggests irregular migrants engage relatively little in transnational activities because of the obstacles associated with their legal and economic statuses. Drawing on participant observation and in-depth interviews with a diverse population of irregular migrants in Belgium and the Netherlands, however, I shall demonstrate in this article that irregular migrants do indeed engage in various transnational activities. Moreover, I argue that a focus on aspirations helps to understand why irregular migrants either do or do not engage in specific transnational activities. Distinguishing between investment, settlement and legalization aspirations, I analyse whether and for what reasons irregular migrants carry out economic, social and political transnational activities. I conclude that future research on transnationalism and on the incorporation of irregular and regular migrants alike could benefit from contextualizing the agency of migrants by taking their aspirations into account.