Over the last decades, the transition to adulthood of young Europeans has become increasingly long. Nevertheless, the existing literature has not comprehensively examined the timing at which events are experienced among recent birth cohorts across European countries; further, the composite role played by ascribed characteristics such as parental socio-economic background and gender remains understudied. The aim of this dissertation is to analyse heterogeneity in the timing of events of the transition to adulthood (i.e., leaving the parental home, entering the labour market, forming a co-residential union, becoming parent), with a focus on gender differences and on the socio-economic characteristics of individuals, their parents, and their partners. The dissertation adopts a longitudinal, comparative, and multilevel perspective, and updates the existing literature by including information about young cohorts (born after 1980) and about the consequences of the COVID-19 pandemic. Drawing on the most recent retrospective and prospective longitudinal data available in Europe (European Social Survey - timing of life module, European Union Statistics on Income and Living Conditions, and German Family Panel pairfam), the empirical contributions analyse: (1) the association between the parental background and the age at leaving home, and its variation across European countries and regions; (2) leaving home trends in Southern Europe during the first year of the COVID-19 pandemic, according to individual and parental economic characteristics; (3) the transition from a non-residential to a co-residential union in Germany, as a function of the economic characteristics of both partners in different-sex relationships; (4) the interplay between parental education and gender on the timing of all events of the transition to adulthood, in comparative perspective.