5 facts about migration and the United Kingdom

Immigration to the United Kingdom has been one of the most important issues driving the debate over whether or not the UK should remain a member of the European Union. Britain’s exit from the EU, or “Brexit,” will be decided in a June 23 referendum, with some seeing an exit as a way to slow immigration into the UK.

Here are five facts about migration into and out of the UK:

1The UK has the fifth-largest immigrant population in the world, at 8.5 million. Between 1990 and 2015, the UK’s immigrant population more than doubled, from 3.7 million. As of 2015, about 13% of the UK’s resident population was foreign-born, comparable to the roughly 14% foreign-born share in the United States.

2As of 2015, the UK’s immigrant population has one of the most diverse groups of origin countries in the world, tying Denmark for the highest diversity score, which measures the distribution of immigrants from different source countries. The top three origin countries of immigrants living in the UK are India (780,000), Poland (700,000) and Pakistan (540,000).

3About a third of the UK’s immigrants (2.9 million, or 34%) were born in other EU countries. By contrast, Luxembourg, at 89%, has the highest share of its immigrant population that is from other EU countries. The UK’s neighbor Ireland also has a higher share (74%) of EU immigrants, as does Germany (44%), the EU country with the highest number of immigrants. Brexit debates have mostly focused on EU immigrants living in the UK.

4In 2015, about 4.9 million people born in the UK lived in other countries, the 10th-largest emigrant population in the world. Overall, about 8% of those born in the UK live outside its borders. By contrast, only about 1% of those born in the U.S. live outside of the United States. Among the 10 countries with the highest number of emigrants, the UK is the only Western European country to appear on the list. Other top origin countries of emigrants include India (15.6 million), Mexico (12.3 million) and Russia (10.6 million).

5Despite its relatively large global emigrant population, as of 2015, only 25% of the UK’s emigrant population lives in other EU countries, the lowest share among EU nations. By contrast, Luxembourg (89%), Slovakia (87%), Romania (87%) and the Czech Republic (84%) have the highest shares of emigrants living in other EU countries. Among the EU nations with the largest populations, about half of France’s (49%) and Germany’s (45%) emigrant populations live in other EU countries.