Family formation has been substantially delayed in recent decades, and birth rates have fallen below the replace-ment rates in many OECD countries. Research suggests that these trends are tightly linked to recent changes in the labor market; however, little is known about the role played by increases in job insecurity. In this paper, I investigate whether the type of employment, stable or temporary, affects the timing of cohabitation and fertility. Using French data on the work and family history of large samples of young adults, I provide evidence that being permanently employed has a much stronger effect than being in temporary employment on the probability of entering a first cohabiting relationship as well as on the probability of having a first child. These findings suggest that increases in age at first cohabitation and at first child can partly be explained by the rise in unemployment and in the share of temporary jobs among young workers.