In 2015, 1.4 million people having citizenship of an EU-28 country migrated to another EU-28 country. The countries that had a large share(more than 50 percent) of EU citizens among the total immigrants into it were Romania, Lithuania, Hungary, Croatia, Latvia, Estonia and Portugal.

In the cases of Romania and Lithuania, a large percentage of this immigration was the return of native born people returning to the countries of their birth. At the same time, these two countries also reported more emigrants than immigrants along with Croatia, Latvia, Portugal and six other countries (total 11 countries with more people leaving than coming in). The 17 remaining countries had more immigrants (incoming) than emigrants (leaving).

As of January 1, 2016, 19.3 million people living in the EU were born in another EU-28 country. The numbers of this group were higher than non-EU born immigrants in Hungary, Ireland, Luxembourg, Slovakia and Cyprus. The number of EU citizens living in an EU country other than the one where they had citizenship was 16 million.

Looking at the countries having large migrant numbers, Germany with 1.44 million immigrants (excluding 58,000 native-born immigrants) in 2015 had 441,000 of them who were born in another EU member state. This was 28.6 percent of the total immigrants in Germany.

Also in 2015, the United Kingdom had 558,500 immigrants(excluding 73,000 native-born immigrants) living on its territory, of whom 258,000 or 40.9 percent were born in another EU member state.

Among the leading countries with emigration in 2015, Germany came first with 347,200, Spain in second at 343,900 while the United Kingdom came third with 299,200 emigrants, with France and Poland making up the fourth and fifth largest respectively on the list.

Calculating the number of people migrating within Europe is often not as black and white as it might first appear. Figures for 2015, as calculated by the Europa Eurostat group, stated that 4.7 million people immigrated to one of the EU member states. However almost 2.8 million emigrants were reported to have left an EU member state. From the 4.7 million group, 2.4 million were estimated to have arrived from Europe but from a country which is not a member of the EU. Of the member states, 17 reported more immigrants than migrants and Germany had the highest number in both categories. Several countries however, including Bulgaria, Ireland, Greece, Spain, Croatia, Cyprus, Portugal, Poland, Romania, Latvia and Lithuania, reported more migration than immigration. Using the term migrate to mean all the people that moved within Europe, either to or from a European country and irrespective of whether they applied for citizenship, the estimates suggest around 7.5 million people.