This article sets out why and how plans to build Europe on mail, both commercially (rates) and symbolically (stamps), were discussed from the end of the 1920s and have failed up to today. The European Conference of Postal and Telecommunication Administrations (CEPT) was created during the intense phase of European integration in the 1950s. In the 1980s it was a key resource for the European Commission for building a Single Market in the telecommunication sector. As this article argues, however, the CEPT did not emerge from the multiple plans for postal integration. Rather, it was a new envelope hiding governance practices inherited from the nineteenth century.