The article examines age as a possible group identity. It sets out to determine which age groups in society today have a stronger sense of identity and the source of that identity, while drawing on the tenets of social psychology and the theories of social identity and optimal distinctiveness. The latter two theories provide insight into the motives for identiﬁcation with social groups, but see different needs at the heart of this identiﬁcation, and thus offer alternative hypotheses of age as a source of status and positive self-image versus age as a source of distinctiveness and a ‘substitute’ source of identity. The analysis is based on representative data for the Czech population over the age of 20 drawn from the European Social Survey Round 4 and the International Social Survey Programme 2003. It shows that self-categorisation into the verbally deﬁned age groups of young, middle-aged, and old is indeed common. It also reveals a much stronger level of peer group self-identiﬁcation among the youngest and oldest respondents, despite the low social status of these age groups. The article closes with a discussion of the varying signiﬁcance age has as a source of social identity and the invalidity of the hypothesis that age group identiﬁcation is dependent on the social status of its members.