Building on 12 months of ethnographic fieldwork among people with Alzheimer’s disease living in Denmark, I argue that the loss of a sense of time caused by Alzheimer’s is not a subjective loss, but rather an intersubjective one. Alzheimer’s disease entails living with desynchronized rhythms, time that can be made painfully explicit, and numbers becoming increasingly tricky to manage. Drawing on Thomas Fuchs’ theory of how individuals live in ‘‘basic contemporality,’’ I explore moments of temporal rupture, and how people with Alzheimer’s challenge their social relations due to their different sense of time. The article contributes to ongoing discussions about belonging. Taking inspiration from Tine Gammeltoft’s description of how belonging entails fragile attempts at being part of something larger, and is thus a joint social practice, I show how one dimension of belonging’s fragility is the inability to be in synch with social time. By proposing the notion of temporal belonging, I suggest that sustaining a sense of belonging is also about being able to participate in the rhythms and tempo of social life.