The socio-economic inclusion of immigrants’ children is a marker to evaluate the ethnic-based mechanisms of transmission of social inequality. Anyway, little is known about these mechanisms and how they operate in countries that only recently arose as migrant destinations, like the Southern European ones. This represents an important gap in the literature, since Southern European countries present peculiar characteristics in terms of patterns of socio-economic assimilation of first-generation migrants, and these peculiarities may also affect their children’s assimilation trajectories. This work aims to fill this gap and provides, for the first time, a comprehensive overview of the migrants’ socio-economic achievement in 9 Western European countries, accounting for the different migrant generations and for their stratification-relevant characteristics. To this purpose, multivariate statistical techniques are applied to the individual data of two Eurostat “ad hoc modules” (2014, 2021) EU Labour Force Survey. Results suggest cross-countries heterogeneities in the patterns under scrutiny.