Using matched employer-employee data, we examine the wage gaps between immigrant and native workers in the Portuguese labour market in the 2002-2008 period. We use the relation between the Gelbach’s and Oaxaca-Blinder’s decompositions to split the unconditional average wage gap as the sum of a composition effect and a wage structure effect. Most of the wage gap is not due to worst endowments of the immigrants but to differences in the returns to those characteristics and to the immigrant status effect. In particular, education and foreign experience of the average immigrants are significantly less valued in the Portuguese labour market. Overall, the wages of immigrants do not fully converge to those of comparable natives as experience in the Portuguese labour market increases. The assimilation rates tend to be stronger in the first years after migration and for immigrants with higher levels of pre-immigration experience. Total immigrants are a heterogeneous group of different nationalities, with immigrants from the EU15 and China starring as the two extreme cases.