This paper examines how young adults make their transition into adulthood and how social policies shape this transitional process. Utilizing an innovative methodology of sequence analysis, cluster analysis and growth curve multilevel models, I investigate the role of standard work and its timing in determining income mobility and co-residential unions in early adulthood in Germany and the UK. The results show that non-standard and late standard careers delay income mobility, compared to beginning standard jobs early. Moreover, delayed entry into standard work is associated with the delayed formation of co-residential unions. Although this process is more prominent in the UK than in Germany, it is similarly strong in the two societies when economic insecurity is on the rise. Furthermore, while in Germany entering into standard employment occurs later than in the UK, in the latter, career marginalization is more pronounced. Gendered life courses exist in both countries and are discussed.