This article examines pathways to adulthood among Dutch cohorts born in the second half of the nineteenth century. Although largely overlooked by previous studies, theory suggests that life courses of young adults born during this period were already influenced by a process of standardization, in the sense that their life courses became more similar over time. Using data from a Dutch registry-based sample, we examine household trajectories: that is, sequences of living arrangements of young adults aged 15–40. Our study shows that for successive cohorts, household trajectories became more similar. We identified six types of trajectories: early death, life-cycle service, early family formation, late family formation, singlehood, and childless but with partner. Over time, early family formation gradually became the "standard" trajectory to adulthood. However, late family formation and singlehood, common pathways within the preindustrial western European marriage pattern, remained widespread among cohorts born in the late nineteenth century. Laboring class youths, farmers' daughters, young people of mixed religious background, and urban-born youngsters were the nineteenth century forerunners of a standard pathway to adulthood.