Although many indicators reflect the marked retreat from marriage occurring in Spain since the 1980s, the diffusion of cohabitation has been slow. The confluence of very low and late fertility, latest‐late marriage, and low cohabitation has been largely regarded as defying the predictions of the second demographic transition and has fueled a debate over the distinctiveness of the Mediterranean model of family formation. Comparative analyses based on the Family and Fertility Survey documented the marginal role of cohabitation in Spain and in the rest of southern European countries by the mid‐1990s. In this research, the authors used more recent data from the 2006 Spanish Fertility, Family and Values Survey (N = 5,750) to reveal that cohabitation has spread significantly among younger cohorts and hence can no longer be considered as playing a marginal role in the family formation process.