This paper concerns belonging in islands. Place-belonging conjures images of feeling at home somewhere, in our case islands. Given the emotionality of belonging, we explore island belonging through emotions. More specifically, we apply the concept of the aquapelago to island belonging and refer to this as aquapelagic belonging. Bringing in emotions, embodied perceptions and mobility, we discuss how these are assembled in island-sea relations to form aquapelagic belonging. In doing so, we draw on qualitative data from fieldwork undertaken in locations where proximity to the sea and access to seaborne mobility is paramount. Our findings demonstrate how certain emotional dispositions and mobility practices emerge in processes of aquapelagic belonging, indicating that mobility is intricately entangled with island belonging. We propose that the interconnected nature of land and sea spaces co-produce emotions of belonging in island spaces. We therefore argue that the concept of aquapelagic belonging lends useful insight to understand what is particular about island belonging. Furthermore, we suggest that attention to mobility, which in this context means navigating land/sea environments, is key to understanding aquapelagic belonging. We conclude that to grasp island belonging, the notion of the aquapelago is relevant and assists in understanding the totality of island relations.