Little research has examined changes in personal identity over different periods of adult development. The aim of the present cross-sectional study was to target these changes through the characterization of the main dimensions in self-defining memories (SDMs; thematic content, specificity, integrative meaning, tension, contamination/redemption, and emotion) and their interactions. Our final sample was composed of 652 healthy French adults aged from 18 to 97 years, divided into four age groups: young adults (n = 163, M = 23.7 years), middle-aged adults (n = 135, M = 44.0 years), young-old adults (n = 178, M = 64.5 years), and old-old adults (n = 176, M = 79.6 years). Participants were asked to recollect three SDMs. A similar pattern of thematic content was observed throughout adulthood, except for relationship narratives were more frequent in the two younger groups. The findings highlighted that specific and integrated SDMs decreased with age and that tension and contaminative sequences were the most frequent in young adults. Redemptive memories did not significantly differ whatever the age of participants. No clear positivity effect was observed with aging. Finally, an analysis of the correlations among the main SDMs' dimensions showed that specificity correlated positively with tension in young adults and integrative meaning with redemption in young and middle-aged participants. We found no significant correlation between specificity and integration in any age group. For the first time, this study sheds new light on lifelong identity adjustments.