According to the guardian: "The Muslim share of Germany’s population could grow from 6.1% to 19.7% between 2016-2050 if high migration continues. The Muslim population in some European countries could triple by 2050.
In the zero migration scenario, the Muslim population in Europe is expected to rise from 4.9% to 7.4%. Apart from Cyprus, which has a high Muslim share (25.4%) due to the historical presence of Turkish Cypriots in the north of the island, France would have Europe’s biggest share of population with 12.7%, up from 8.8%.
In the medium migration scenario - perhaps the most likely - Sweden would have the biggest share of population at 20.5%. The UK’s share would rise from 6.3% in 2016 to 16.7%. Finland’s Muslim share would grow from 2.7% to 11.4% and most western European countries would face a big jump.
If high migration continues until 2050, Sweden’s Muslim share will grow to 30.6%, Finland’s to 15% and Norway’s to 17%. In eastern Europe, most countries will continue to have a relatively low Muslim share of population, with only Hungary and Greece seeing significant increases from 2016."