In this article we address one of the most prominent questions in historical sociology: did economic modernization in the nineteenth century lead to societal openness? In an attempt to answer the question we examine the chances for lower-class grooms of marrying upwardly in five Belgian cities (Aalst, Leuven, Ghent, Verviers, and Liège). Our findings show that there is no support for a meritocracy hypothesis. The chances of marrying out of the lower classes did not increase, in either absolute or relative terms. Social closure strategies were efficient in that they apparently prevented upward marital mobility for lower-class grooms. As these findings were measured in a highly advanced economic context, this study casts strong doubts on the relationship between economic modernization, meritocracy, and marital mobility, at least for the nineteenth century.