BACKGROUNDThe variability of age at first marriage reflects how likely people are to marry at similar ages. As the family institution changes in Taiwan, it may have experienced a destandardization in the life course. With the second demographic transition, this may imply a more dispersed age at first marriage; however, collectivism, the ideology of formal marriage, and the strong association between marriage and fertility may constrain this variability.OBJECTIVE We examine changes in variability of age at first marriage for women across birth cohorts and education levels in Taiwan.METHODSThis study uses the Women’s Marriage, Fertility, and Employment Survey in Taiwan. We employ regression models to investigate how women’s birth cohort and education level affect their relative timing of first marriage. RESULTS The results show that age variability is widening in recent cohorts in Taiwan. However, unlike the findings in Western societies, the trend is consistent across education levels, and highly-educated women in recent cohorts have a relatively restricted the variability of age at first marriage.CONCLUSIONSThe findings suggest that the variability of women’s age at first marriage in Taiwan is still significantly affected by the strong association between marriage and fertility. CONTRIBUTION The findings demonstrate that destandardization in the life course and the second demographic transition in East Asian contexts differs from that seen in Western societies.