That year, a total of 1275 people became Bulgarian citizens.
Of this sum, the largest number were from Ukraine, 17.6 percent, followed by Russians, 16.8 percent, and people from Turkey, 14 percent, Eurostat said.
Bulgaria was below the EU average for the naturalisation rate – meaning the ratio of the number of people who acquired the citizenship of a country during a year over the stock of foreign residents in the same country at the beginning of the year.
In Bulgaria, the naturalisation rate was less than two out of 100, compared with an average naturalisation rate in the EU of 2.4 out of 100.
Eurostat said in its report, released on April 21 2017, that in 2015, about 840 000 people acquired citizenship of a member state of the EU, down from 890 000 in 2014 and 980 000 in 2013.
Since 2010, more than five million people in total were granted a citizenship of an EU country. Of the total number of people obtaining the citizenship of one of the EU member states in 2015, 87 percent were non-EU citizens.
The largest group acquiring citizenship of an EU member state in 2015 was citizens of Morocco (86 100 people, of whom 88 percent acquired citizenship of Italy, Spain or France), ahead of citizens of Albania (48 400, 96 percent acquired citizenship of Italy or Greece), Turkey (35 000, 56 percent acquired German citizenship), India (31 000, almost 60 percent acquired British citizenship), Romania (28 400, half acquired Italian citizenship), Pakistan (26 300, half acquired British citizenship) and Algeria (22 500, over three-quarters acquired French citizenship).
Moroccans, Albanians, Turks, Indians, Romanians, Pakistanis and Algerians represented together a third (33 percent) of the total number of people who acquired citizenship of an EU country in 2015. Romanians (28 400 people) and Poles (17 800) were the two largest groups of EU citizens acquiring citizenship of another EU member state.
In 16 EU countries, about 90 percent or more of people who obtained citizenship in 2015 were non-EU citizens: Estonia, Lithuania and Romania (all 100 percent), Bulgaria (99 percent), Spain (98 percent), Latvia (97 per cent), Greece and Portugal (both 96 percent), the Netherlands, Poland and Slovenia (all 94 percent), Denmark (93 percent), France and Croatia (both 90 per cent) as well as Italy and the UK (both 89 per cent).
In contrast, Luxembourg (79 percent) and Hungary (72 percent) were the only EU countries where the majority of people acquiring citizenship in 2015 were citizens of another EU member state.
At EU level, 87 percent (or 732 200 new citizens) of those granted citizenship were non-EU citizens, and 12 percent (104 900 new citizens) of another EU member state, Eurostat said.