State & society - Population - Holders of dual citizenship: differences between microcensus and population census results - Federal Statistical Office (Destatis)
Against the background of recent developments in Turkey, politicians in Germany are currently debating the issue of dual citizenship again. The results of the microcensus show that roughly 1.8 million people with dual citizenship were living in Germany in 2015.
1.7 million people with dual citizenship were holders of both the German and another foreign citizenship, while 107,000 people had two foreign citizenships. Among the German people with dual citizenship those with a Turkish passport formed the largest group (246,000). They were followed by people from the Russian Federation (228,000) and Poland (220,000).
These results differ widely from the data obtained in the 2011 Census. According to the population census results, the number of people with dual citizenship was roughly 4.3 million on the Census reference day (9 May 2011). Approximately 690,000 people with German citizenship had an additional Polish passport, 570,000 a Russian passport and 530,000 a Turkish passport.
While there is a trend towards undercoverage of people with dual citizenship in the microcensus data, it can be assumed that the relevant number in the population census is too high. Please see the article on "Wie viele Menschen in Deutschland besitzen eine doppelte Staatsbürgerschaft?" for more information on the reasons for these differences.