In this article, categorisation based on origins is investigated in the Dutch census reports produced between 1899 and 2018. Through this analysis, I will argue that the conceptual pair of autochthon and allochthon (until 2017 used to describe ‘native’ and ‘non-native’ Dutch people) is not a social construct, but rather a sociotechnical construct. Through this analysis, it becomes clear that where the category of the ‘foreigner’ at the beginning of the twentieth century was mainly related to a passport and place of birth, later national origins became a racially tainted concept. Pre-1980, counting machines at CBS only counted people’s information as selfdescribed; since 1980, computers have determined the identity of Dutch citizens. Today, governmental statistics based on the origins of Dutch people are available online for free and can be used by third parties for a variety of applications. Through this historical analysis, it becomes clear that the current practices are not the ‘standard’ way of categorisation, but rather one of the possibilities that are historically, socially and technologically situated.