Between 2011 and 2021 more than 8.5 million immigrants have acquired the citizenship of a European country, and most of them (close to 93%) have naturalized in a EU14 country. The annual flow of new citizens has in general increased through the 2010s, as we show in Figure 1, which displays the annual number of naturalizations over the time period 2011-2021 across different aggregates of European countries. Overall, according to Eurostat data, there were about 905 thousand naturalizations across European countries in 2021, a 40% increase relative to the 648 thousand naturalizations in 2011. Besides 2021, a second major annual peak of naturalizations happened in 2016, when more than 900 thousand immigrants naturalized across the whole Europe. Two thirds of all the naturalizations occurred in Europe between 2011 and 2021 happened in the five EU countries with the highest GDP (EU5): Germany, France, Italy, Spain and the Netherlands.
Figure 1: Naturalizations in European countries have been increasing over time
Naturalizations over the time period 2011-2021
Among European countries, Spain stands out for having naturalized the highest number of immigrants over these ten years, slightly more than 1.4 million, followed by Italy (1.37 million), Germany (1.27 million) and France (1.2 million). Figure 14 provides some insight on the annual breakdown of these naturalizations for the 10 European countries that naturalized the highest number of between 2011 and 2021. While Germany and France do not display much variation across years, Spain appears to be the main driver of the spike in naturalization that occurred during 2013 and 2014, with over double the naturalizations that took place in 2012.
Similarly, even if to a lesser extent, Italy is the country that displays the sharpest increase in naturalizations over the period 2015 and 2016, respectively 37% and 55% higher than 2014. In both cases, however, the increase has been largely temporary.
Figure 2: Italy and Spain are the main drivers of the spikes in naturalizations of 2013-2016
Naturalizations by year for the ten European countries with most naturalizations in 2011 – 2021
European mobile citizens account for about one third of all immigrants in other EU countries. Yet, as Figure 3 shows, they account for only 15% of the naturalizations over the periods 2011-2021. Conversely, immigrants from Africa and the Middle East, who make up overall 25% of all immigrants in the EU, account for about 36% of all naturalizations. In other words, EU immigrants’ probability of acquiring the citizenship of their country of residence is less than one third than for African migrants. Likewise, Latin American immigrants account for almost 14% of all naturalizations, but only for 10% of all resident immigrants in Europe. These differences can be explained by several factors, like for instance differences in average length of stay in the current country of residence, but certainly a key role is played by the different returns that citizenship of a EU country may have for immigrants from countries outside of the European Union – relative to other migrants who are already EU nationals. We analyse later the economic returns to citizenship and how they differ across different migrant groups.
Figure 3: Less than 15% of naturalized citizens were originally from another EU country
Naturalizations in Europe between 2011 and 2021, by origin
However, focusing once again on the 10 European countries with the highest number of naturalizations, there is a significant degree of heterogeneity with regard to naturalized immigrants’ origins, which partly reflects differences in countries of origin mix across destination countries (Figure 4). In particular, over 50% of the migrants becoming Spanish nationals are from South and Central America (52%), while about two thirds of new citizens in France (67%) and in Germany (60%) were born in Africa or Middle East and in Europe, respectively. The country of birth mix of new Italian citizens is instead more balanced with 40% from another European country and an additional 24% from North Africa and the Middle East.
Figure 4: Significant cross-country heterogeneity with regard to origin of new citizens
Naturalizations by origin for the ten European countries with most naturalizations in 2011 – 2021
Over the past decade, about 2.3% of all foreign citizens in EU countries have acquired the nationality of their current country of residence in every year (Figure 5). Sweden stands out as the country with most naturalizations per year (relative to the size of its foreign-born population): more than 7.6% of immigrants in Sweden naturalized every year, which amounts to more than three times the European average and 1.5 times the rate of Portugal (5.1%), the
second European country in terms of naturalizations relative to its immigrant population. At the other end of the spectrum, countries like Estonia (0.58%), Czech Republic (0.62%), Croatia (0.62%), Lithuania (0.68%), Latvia (0.69%) and Austria (0.74%) have naturalized on average less than 1% of their foreign population in every year. Despite the high number of citizenship acquisitions we have previously noted, the annual naturalization rates of Italy (2.6%), Spain (2.7%) and France (2.4%) are pretty much aligned with the European average, which indicates that their high number of naturalizations reflects the large size of their immigrant populations, rather than a high propensity to naturalization of its foreign residents, while Germany is remarkably below the EU average at only 1.4%.
Figure 5: More than 2% of immigrants naturalize in Europe every year
Average share of non-citizens that were naturalized each year between 2011 and 2021
These annual naturalization rates, cumulated over the eleven years considered, imply that a significant share of the foreign population has acquired citizenship of their host country over the past decade. We show this in Figure 6, which displays the ratio of the total number of individuals who acquired the nationality of their current country of residence between 2011 and 2021 to the initial stock of foreign nationals in each country in 2011. Overall, across Europe the number of naturalized immigrants amounts to more than one fourth (29.4%) of the foreign national residents in 2011. As expected, given the figures on annual flows of naturalizations, Sweden stands out as having naturalized over a decade a number of immigrants, which is equivalent to about the size of its 2011 stock, almost twice as much as Finland (56%) and Portugal (57%).
Figure 6: Over the past decade, Europe has naturalized more than 25% of its foreign born residents
Naturalizations over the period 2011-2021 as a share of resident non-citizens in 2011
