Abstract The aim of this article is to analyse and compare the census statistics on Muslims in Europe provided by the Yearbook of Muslims in Europe with anti-Muslim estimates of the possible numbers of Muslims in Europe in order to give a comprehensive picture of how many individuals actually identify themselves as Muslims. Contrary to popular figures estimating that there are approximately forty to fifty million Muslims living in Europe (including Russia, but leaving out Turkey) the official census data provided by nineteen countries in the Yearbook gives a figure closer to five million. The findings in my article are based on the available censuses from 2000 until today (that is, summer 2012), and the results give a presentation of census statistics on individuals who identify themselves as Muslims in Europe. The results from the Yearbook of Muslims in Europe are critically discussed and related to estimates and popular assumptions about the number of Muslims in Europe that circulate in the media, especially among anti-Muslim writers who adhere to the so-called Eurabia theory. In conclusion it is clear that there is a large gap between popular anti-Muslim estimates of the number of Muslims and the figures presented in official census data. It is argued that this gap may have a negative impact on how Islam and Muslims are framed, discussed and debated in Europe today.