Phenomenological analyses of ageing and old age have examined themes such asalterity, finitude, and time, not seldom from the perspective of “healthy” aging.Phenomenologists have also offered detailed analyses of lived experiences of illnessincluding lived experiences of dementia. This article offers a phenomenological account of what we label as entering the grey zone of aging between “healthy” agingand aging with a disease. This account is developed through a qualitative phenomenological philosophy analysis of elderly persons’ lived experiences of being testedfor dementia through primary care in Sweden, i.e., within a cultural context wheredementia commonly is understood as a frightening a loss of self even though thisunderstanding also is questioned. To enter this grey zone of aging, we argue, doesnot dissolve dynamic self-becoming but can involve an experience of oneself as being old. Further, in the grey zone, the self experiences itself as neither fully healthynor as having a disease, and as needing to negotiate and live this ambiguity. Toenter this grey zone is to enter an affectively charged, sociocultural and medicalized zone, and while the self can still act in different ways within it, staying in thegrey zone can result in a re-orientation in the self’s mode of being, in ways thatare thoroughly beyond its control. To stay in the grey zone can have detrimentaleffects on the self, even though the self does not have a disease: the self can become“stuck” in a reflective mode of attending to embodiment, aging, health, and disease.