In France as in many other Western European countries, the purported concentration of large Muslim populations in disadvantaged areas at the outskirts of major cities has been associated with public and scholarly concerns for failed integration, but little spatial data exists for purposes of empirical study. Relying on a unique geolocated dataset built from online repositories of Muslim places comprising halal butcher shops, prayer spaces, religious schools and bookstores, I use a geographic information system to map Islamic institutions in the Paris metropolitan area. Contrary to the religious segregation narrative, the presence of Islamic institutions is widespread within the city. Using census income data aggregated by neighborhoods however, I show that the spatial distribution of Muslim institutions matches broader dynamics of income segregation within the entire metropolitan area. In spite of urban mainstreaming suggested by a substantial presence within the city proper, the spatial integration of Islam remains incomplete.