Objectives. Research on age-related changes in personal networks has found compelling evidence for socioemotional selectivity theory and exchange theory holding that older adults experience a decline in less emotionally close nonkin relations as they age. However, recent societal developments are likely to have increased the salience of nonkin relations. We hypothesize that age-related decline in the proportion of nonkin in personal networks has been delayed or is slower in late birth cohorts of older adults compared with earlier cohorts. Method. Seven observations by the Longitudinal Aging Study Amsterdam covering a time span of 17 years since 1992 were analyzed using multilevel regression analysis. The sample had 12,949 person-year observations from 3,516 respondents born between 1908 and 1937. Results. Age-related decline in the proportion of nonkin is absent for cohorts born after 1922 and large for cohorts born in 1922 and before. Mediating variables for health and other resources did not explain cohort differences in age-related change. Discussion. The salience of nonkin relationships is likely to have increased due to societal changes, resulting in absence or delay of decline in later cohorts. The findings raise the need for a reevaluation of old age and the creation of new theoretical perspectives. © The Author 2013.