Previous studies on intermarriage in Europe have focused mainly on marriages between migrants from non-western origin and partners from the EU settlement country. This paper examines intermarriage among EU migrants and the native population in four countries of settlement: Spain, Belgium, the Netherlands and Switzerland. It is relevant to know who marries whom and what patterns of intermarriage among EU citizens are observed since European migrants are an important part of the migrants in each of the four settlement countries. Taking an international comparative approach can highlight how and to what extent the same patterns and factors are found to be relevant in different European countries. This study can advance our understanding of the trends in EU intermarriages, their changes over time and factors involved. The study draws from data including the total population in each of the four countries by combining vital statistics, census and register data over the period from 1989 to 2009. Bi-national marriages between two spouses of different EU descent are assumed to be an important indicator as well as driver for social cohesion within the EU.